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Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations

The Company focuses on infrastructure and is Building a Strong America® by providing essential products and services through its regulated energy delivery and construction materials and services businesses. The Company and its employees work hard to keep the economy of the United States moving with the products and services provided, which include powering and connecting homes, factories, offices and stores; and building roads, highways, data infrastructure and airports.

The Company's two-platform business model, regulated energy delivery and construction materials and services, are each comprised of different operating segments. Most of these segments experience seasonality related to the industries in which they operate. The two-platform approach helps balance this seasonality and the risks associated with each type of industry. The Company is authorized to conduct business in 45 states and during peak times has over 15,600 employees. The Company’s organic investments are strong drivers of high-quality earnings growth and continue to be an important part of the Company’s growth story. Management believes the Company is well positioned in the industries and markets in which it operates.

Impact of the COVID-19 pandemic on the Company

In March 2020, the World Health Organization declared the outbreak of COVID-19 a pandemic, and the President of the United States declared the COVID-19 outbreak as a national emergency. Most of the Company's products and services are considered essential to our country and our communities; therefore, operations have generally been permitted to proceed with increased social distancing measures and hygiene practices for its employees. While the Company has experienced some inefficiency impacts, including operation suspensions and interruptions at some locations to carry out preventative measures or in response to instances of positive tests, the impacts have not been material. For more information on specific impacts to each of the Company's business segments, see the following discussions in each business segment's Outlook section.

In March 2020, the President of the United States signed into law the CARES Act in response to the COVID-19 pandemic. The CARES Act provided economic relief and stimulus to support the national economy during the pandemic, including support for individuals and businesses affected by the pandemic and economic downturn. The CARES Act allowed businesses to defer payment of the employer portion of social security taxes incurred through the end of 2020. At December 31, 2020, the Company had deferred approximately $56.7 million in payroll taxes related to this provision. The Company is required to pay 50 percent of the payroll taxes deferred under this provision by the end of 2021 and the remaining balance by the end of 2022.

The Company evaluated its planned capital projects and delayed certain expenditures in 2020 to provide additional financial flexibility and to ensure projects will provide acceptable returns on investment. In addition, the Company established a task force to monitor developments related to the pandemic and implemented procedures to protect employees. Many employees that have the capacity to work from home continue to do so as the Company has delayed return to work processes for certain office employees due to COVID-19 cases in some operating regions. The Company has also enacted additional physical and cybersecurity measures to safeguard systems for remote work locations.

Although there have been logistical and other challenges as a result of COVID-19, there were no material adverse impacts on the Company's results of operations for the year ended December 31, 2020. The Company continues to adjust its business in response to the pandemic while positioning for an economic rebound and potential opportunities to enhance its competitive position. The situation surrounding COVID-19 remains fluid and the potential for a material adverse impact on the Company increases the longer the virus impacts the level of economic activity in the United States. Due to the uncertainty of the economic outlook resulting from the COVID-19 pandemic, the Company continues to monitor the situation closely. For more information on the possible impacts, see Item 1A - Risk Factors.

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Consolidated Earnings Overview

The following table summarizes the contribution to the consolidated income by each of the Company's business segments.

(In millions, except per share amounts)

Income (loss) from discontinued operations, net of tax (.3) .3 2.9

Earnings per share - basic:

Income from continuing operations $ 1.95 $ 1.69 $ 1.38

Discontinued operations, net of tax — — .01

Earnings per share - basic $ 1.95 $ 1.69 $ 1.39

Earnings per share - diluted:

Income from continuing operations $ 1.95 $ 1.69 $ 1.38

Discontinued operations, net of tax — — .01

Earnings per share - diluted $ 1.95 $ 1.69 $ 1.39

2020 compared to 2019 The Company's consolidated earnings increased $54.7 million or 16 percent in 2020 as compared to 2019.

The Company's earnings were positively impacted by increased earnings across all of the Company's businesses in 2020. The construction materials and contracting business experienced an increase in gross margin, primarily resulting from favorable weather conditions and higher realized materials margins on asphalt and asphalt-related products and ready-mixed concrete, as well as most other product lines. The construction services business also experienced an increase in gross margin as a result of higher inside and outside specialty contracting workloads, partially due to the businesses acquired, as well as hospitality projects, high-tech projects and natural disaster recovery work. The pipeline business experienced increased transportation volumes and revenues, largely related to organic growth projects, as well as higher storage-related revenues as a result of stronger demand for storage services. In addition, approved rate recovery positively impacted earnings at the electric and natural gas distribution businesses.

2019 compared to 2018 The Company's consolidated earnings increased $63.2 million or 23 percent in 2019 as compared to 2018.

Positively impacting the Company's earnings was an increase in gross margin at the construction services business, largely resulting from higher inside and outside specialty contracting workloads. Also contributing to the increase in earnings was an increase in gross margin at the construction materials and contracting business as a result of strong economic environments in certain states, as well as contributions from the businesses acquired and an increase in gains recognized on asset sales. The electric business also positively impacted earnings primarily due to approved rate relief in Montana and recovery of the investment in the BSSE project placed into service in the first quarter of 2019. Higher returns on the Company's benefit plan investments also increased earnings across all businesses. At the pipeline business, increased rates and volumes of natural gas being transported through its pipeline were mostly offset by the absence of a $4.2 million income tax benefit recorded in 2018 relating to the reversal of a regulatory liability recorded in 2017 based on a FERC final accounting order and higher depreciation, depletion and amortization expense.

A discussion of key financial data from the Company's business segments follows.

Business Segment Financial and Operating Data

Following are key financial and operating data for each of the Company's business segments. Also included are highlights on key growth strategies, projections and certain assumptions for the Company and its subsidiaries and other matters of the Company's business segments. Many of these highlighted points are "forward-looking statements." For more information, see Part I - Forward-Looking Statements. There is no assurance that the Company's projections, including estimates for growth and changes in earnings, will in fact be achieved. Please refer to assumptions contained in this section, as well as the various important factors listed in Item 1A - Risk Factors. Changes in such assumptions and factors could cause actual future results to differ materially from the Company's growth and earnings projections.

For information pertinent to various commitments and contingencies, see Item 8 - Notes to Consolidated Financial Statements. For a summary of the Company's business segments, see Item 8 - Note 17.

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Electric and Natural Gas Distribution

Strategy and challenges The electric and natural gas distribution segments provide electric and natural gas distribution services to customers, as discussed in Items 1 and 2 - Business Properties. Both segments strive to be top performing utility companies measured by integrity, employee safety and satisfaction, customer service and shareholder return, while providing safe, environmentally friendly, reliable and competitively priced energy and related services to customers. The Company is focused on cultivating organic growth while managing operating costs and monitoring opportunities for these segments to retain, grow and expand their customer base through extensions of existing operations, including building and upgrading electric generation, transmission and distribution, and natural gas systems, and through selected acquisitions of companies and properties with similar operating and growth objectives at prices that will provide stable cash flows and an opportunity to earn a competitive return on investment. The continued efforts to create operational improvements and efficiencies across both segments promotes the Company's business integration strategy. The primary factors that impact the results of these segments are the ability to earn authorized rates of return, the cost of natural gas, cost of electric fuel and purchased power, weather, competitive factors in the energy industry, population growth and economic conditions in the segments' service areas.

The electric and natural gas distribution segments are subject to extensive regulation in the jurisdictions where they conduct operations with respect to costs, timely recovery of investments and permitted returns on investment, as well as certain operational, environmental and system integrity regulations. Legislative and regulatory initiatives to increase renewable energy resources and reduce GHG emissions could impact the price and demand for electricity and natural gas, as well as increase costs to produce electricity and natural gas. The segments continue to invest in facility upgrades to be in compliance with the existing and future regulations. To assist in the reduction of regulatory lag in obtaining revenue increases to align with increased investments, tracking mechanisms have been implemented in certain jurisdictions, as further discussed in Items 1 and 2 - Business Properties and Item 8 - Note 20.

In September 2019, the Pipeline and Hazardous Materials Safety Administration issued a rule for additional regulations to strengthen the safety of natural gas transmission and storage facilities and hazardous liquid pipelines. The natural gas segment has implemented procedure changes for the initial requirements and continues to evaluate procedure changes necessary for the additional requirements effective July 1, 2021.

State implementation of pollution control plans to improve visibility at Class I areas, such as national parks, under the EPA's Regional Haze Rule could require the owners of Coyote Station to incur significant new costs. If the owners decide to incur such costs, the costs could, dependent on determination by state regulatory commissions on approval to recover such costs from customers, negatively impact the Company's results of operations, financial position and cash flows. The NDDEQ's state implementation plan is due to be submitted to the EPA by July 2021. The Company expects the NDDEQ to draft a state implementation plan and share its controls selection with federal land managers of the National Park Service and the United States Fish and Wildlife Service in early 2021. Additionally, the Company is one of four owners of Coyote Station and cannot make a unilateral decision on the plant's future. The Company could be negatively impacted by the decisions of the other owners.

The electric and natural gas distribution segments are facing increased lead times on delivery of certain raw materials used in electric transmission and natural gas pipeline projects. Long lead times are attributable to increased demand for steel products from pipeline companies as they respond to the United States Department of Transportation Pipeline System Safety and Integrity Plan, as well as delays in the manufacturing of electrical equipment as a result of the COVID-19 pandemic, including delays in trucking times and issuance of permits for large and heavy loads. The Company continues to monitor the material lead times and is working with manufacturers to proactively order such materials to help mitigate the risk of delays due to extended lead times.

The ability to grow through acquisitions is subject to significant competition and acquisition premiums. In addition, the ability of the segments to grow their service territory and customer base is affected by regulatory constraints, the economic environment of the markets served and competition from other energy providers and fuels. The construction of any new electric generating facilities, transmission lines and other service facilities is subject to increasing costs and lead times, extensive permitting procedures, and federal and state legislative and regulatory initiatives, which will likely necessitate increases in electric energy prices.

Revenues are impacted by both customer growth and usage, the latter of which is primarily impacted by weather, as well as impacts associated with commercial and industrial slow-downs, including economic recessions, and energy efficiencies. Very cold winters increase demand for natural gas and to a lesser extent, electricity, while warmer than normal summers increase demand for electricity, especially among residential and commercial customers. Average consumption among both electric and natural gas customers has tended to decline as more efficient appliances and furnaces are installed, and as the Company has implemented conservation programs. Natural gas weather normalization and decoupling mechanisms in certain jurisdictions have been implemented to largely mitigate the effect that would otherwise be caused by variations in volumes sold to these customers due to weather and changing consumption patterns on the Company's distribution margins, as further discussed in Items 1 and 2 - Business Properties.

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Earnings overview - The following information summarizes the performance of the electric segment.

(Dollars in millions, where applicable)

Taxes, other than income .6 .6 .7 — % (14.3) %

Operating expenses:

Retail sales (million kWh):

Average cost of electric fuel and purchased power per kWh $ .019 $ .023 $ .022

Adjusted gross margin is a non-GAAP financial measure. For additional information and reconciliation of the non-GAAP adjusted gross margin attributable to the electric segment, see the Non-GAAP Financial Measures section later in this Item.

2020 compared to 2019 Electric earnings increased $800,000 as a result of:

Adjusted gross margin: Comparable to the prior year. The adjusted gross margin was positively impacted by higher rates of $2.8 million, including approved rate relief resulting in $2.0 million additional revenue. These increases were offset by lower retail sales volumes of 3.3 percent across all customer classes due to warmer weather and slow-downs as a result of the COVID-19 pandemic.

Operation and maintenance: Decrease of $4.4 million, largely due to lower generation station expenses of $3.5 million and lower payroll and other employee-related costs of approximately $1.5 million. Partially offsetting the decreases were increased bad debt expense of $500,000 as a result of the COVID-19 pandemic, as discussed later.

Depreciation, depletion and amortization: Increase of $4.3 million, largely from an increase in asset base driven by capital expenditures, which include transmission projects, and higher depreciation rates implemented from a Montana rate case of $1.2 million.

Taxes, other than income: Increase of $700,000, from higher property taxes in certain jurisdictions.

Other income: Increase of $3.8 million, largely attributable to an out-of-period adjustment of $2.5 million in the fourth quarter of 2020 related to previously overstated benefit plan expense, as discussed in Item 8 - Note 1, and the absence of the write-down of a non-utility investment in the second quarter of 2019 for $1.2 million, as discussed in Item 8 - Note 8. Lower 2020 pension expense also contributed to the increase in other income.

Interest expense: Increase of $1.4 million driven by higher short-term debt balances.

Income tax benefit: Decrease of $1.0 million, largely due to higher income before income taxes.

2019 compared to 2018Electric earnings increased $7.8 million as a result of:

Adjusted gross margin: Increase of $10.8 million, primarily due to an increase in revenues. The revenue increase was driven by implemented regulatory mechanisms, which include approved Montana interim and final rates and recovery of the investment in the BSSE project placed into service in the first quarter of 2019. Also contributing to the increase was the absence in 2019 of a transmission formula rate adjustment

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recognized in the third quarter of 2018 for decreased costs on the BSSE project. These increases were partially offset by lower retail sales volumes of 1.2 percent across all major customer classes.

Operation and maintenance: Increase of $2.7 million, primarily resulting from higher payroll-related costs, partially offset by lower material expenses across all locations.

Depreciation, depletion and amortization: Increase of $7.7 million as a result of increased property, plant and equipment balances including the BSSE project, as previously discussed, and other capital projects, as well as a reserve for certain costs related to the retirement of three aging coal-fired electric generating units, as discussed in Item 8 - Note 6, which is offset in income taxes.

Taxes, other than income: Increase of $1.6 million, primarily from higher property taxes in certain jurisdictions.

Other income: Increase of $2.2 million, largely the result of higher returns on the Company's benefit plan investments, partially offset by the write-down of a non-utility investment in the second quarter of 2019, as discussed in Item 8 - Note 8.

Interest expense: Decrease of $600,000 driven by higher AFUDC, which resulted in more interest being capitalized on regulated construction projects.

Income tax benefit: Increase of $6.2 million, largely due to increased production tax credits, as well as increased excess deferred tax amortization.

Earnings overview - The following information summarizes the performance of the natural gas distribution segment.

(Dollars in millions, where applicable)

Operating expenses:

Depreciation, depletion and amortization 84.6 79.6 72.5 6.3 % 9.8 %

* NM - not meaningful

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Volumes (MMdk)

Retail sales:

Transportation sales:

Average cost of natural gas per dk $ 3.91 $ 3.86 $ 4.04

Adjusted gross margin is a non-GAAP financial measure. For additional information and reconciliation of the non-GAAP adjusted gross margin attributable to the natural gas distribution segment, see the Non-GAAP Financial Measures section later in this Item.

2020 compared to 2019 Natural gas distribution earnings increased $4.5 million as a result of:

Adjusted gross margin: Increase of $10.4 million, largely the result of $6.8 million in approved rate recovery in certain jurisdictions, higher basic service charges of $2.1 million due to customer growth of 2 percent and increased property tax tracker revenue of $1.7 million, which offsets the property tax expense below. Slightly offsetting the increases was a decrease in retail sales volumes of 7.4 percent across all customer classes due to warmer weather and slow-downs as a result of the COVID-19 pandemic, which was largely offset by weather normalization and decoupling mechanisms in certain jurisdictions.

Operation and maintenance: Increase of $400,000, primarily related to increased contract services, largely $1.2 million for the write-off of an abandoned project in the third quarter of 2020, and increased software expenses. Partially offsetting the increase was lower employee-related costs of $1.6 million as a result of the COVID-19 pandemic.

Depreciation, depletion and amortization: Increase of $5.0 million, primarily from an increase in asset base driven by capital expenditures, which include system safety and reliability enhancements and other growth projects.

Taxes, other than income: Increase of $1.1 million due to higher property taxes in certain jurisdictions of $1.7 million, partially offset by lower payroll taxes.

Other income: Increase of $6.3 million, largely driven by an out-of-period adjustment of $4.4 million in the fourth quarter of 2020 related to previously overstated benefit plan expenses, as discussed in Item 8 - Note 1, and lower 2020 benefit plan expenses of approximately $2.2 million. The absence of the write-down of a non-utility investment of approximately $800,000 in the second quarter of 2019, as discussed in Item 8 - Note 8, also contributed to the increase in other income. Partially offsetting the increases was a decrease in interest income of $1.5 million related to the recovery of purchased gas cost adjustment balances.

Interest expense: Increase of $1.3 million, primarily attributable to increased long-term debt balances, partially offset by lower short-term borrowings.

Income tax expense: Increase of $4.4 million, as a result of the increase in income before taxes and permanent tax adjustments.

2019 compared to 2018 Natural gas distribution earnings increased $1.8 million as a result of:

Adjusted gross margin: Increase of $17.4 million, primarily driven by an increase in retail sales volumes of 9.9 percent related to all customer classes due to colder weather, partially offset by weather normalization and conservation adjustments in certain jurisdictions, and approved rate recovery in certain jurisdictions. The adjusted gross margin was also positively impacted by higher rate realization due to higher conservation revenue, which offsets the conservation expense in operation and maintenance expense.

Operation and maintenance: Increase of $11.6 million, largely related to higher payroll-related costs, as well as higher conservation expenses being recovered in revenue. The increase was partially offset by lower contract services, which includes the absence of the prior year's recognition of a non-recurring expense related to the approved WUTC general rate case settlement in the second quarter 2018.

Depreciation, depletion and amortization: Increase of $7.1 million, primarily as a result of increased property, plant and equipment balances.

Taxes, other than income: Increase of $1.8 million due to higher property taxes in certain jurisdictions and increased payroll taxes.

Other income: Increase of $7.0 million, largely resulting from higher returns on the Company's benefit plan investments and increased interest income related to higher gas costs to be collected from customers. Partially offsetting these increases was a write-down of a non-utility investment in the second quarter of 2019, as discussed in Item 8 - Note 8.

Interest expense: Increase of $4.8 million, largely resulting from increased debt balances to finance higher gas costs to be collected from customers.

Income tax expense: Decrease of $2.7 million, largely due to increased permanent tax benefits related to the Company's benefit plan investments.

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OutlookThe Company continues to assess the impacts of the COVID-19 pandemic on its operations and is committed to providing safe and reliable service while ensuring the health and safety of its employees, customers and the communities in which it operates. In response to the pandemic, the Company instituted certain measures to help protect its employees from exposure to COVID-19 and to curb potential spread of the virus in customer homes and facilities, including suspension of disconnects due to nonpayment of bills. The Company also waived late payment fees effective April 1, 2020, to help customers experiencing financial hardships. As a consequence of the suspended disconnects and waived late fees, the Company's cash flows and collection of receivables have been affected. The Company reinstated disconnects and late payment fees in five of its eight states effective September 1, 2020, and the Company reinstated disconnects and late payment fees to certain customer classes in another two states effective January 1, 2021. The Company has experienced some impacts to its commercial and industrial electric and natural gas loads associated with reduced economic activity due to the COVID-19 pandemic and oil price impacts, as further discussed below. The Company expects this downward trend on demand to continue throughout the pandemic. The Company temporarily implemented cost containment measures in response to the COVID-19 pandemic, including reduced employee travel and temporary delays in training for employees, as well as delays in filling open positions and contract work. The Company has filed requests for the use of deferred accounting for costs related to the COVID-19 pandemic in most of the jurisdictions in which it operates; the Company has deferred an immaterial amount related to the pandemic to date. The Company's outstanding filings by jurisdiction related to the COVID-19 pandemic are discussed in Item 8 - Note 20.

The Company expects these segments will grow rate base by approximately 5 percent annually over the next five years on a compound basis. Operations are spread across eight states where the Company expects customer growth to be higher than the national average. In 2020 and 2019, these segments experienced retail customer growth of approximately 1.8 percent each year and expects customer growth to continue to average 1 percent to 2 percent per year. This customer growth, along with system upgrades and replacements needed to supply safe and reliable service, will require investments in new and replacement electric and natural gas systems.

These segments are exposed to energy price volatility. Rate schedules in the jurisdictions in which the Company's natural gas distribution segment operates contain clauses that permit the Company to file for rate adjustments for changes in the cost of purchased gas. Although changes in the price of natural gas are passed through to customers and have minimal impact on the Company's earnings, the natural gas distribution segment's customers benefit from lower natural gas prices through the Company's utilization of storage and fixed price contracts. Additionally, the Company has implemented risk mitigation measures to minimize the price volatility associated with natural gas costs through derivative contracts at Cascade. For further discussion on the Company's derivative instruments, see Item 8 - Note 2. Demand for the Company's regulated energy delivery services could be impacted by reduced oil and natural gas exploration and production activity. The Company continues to monitor natural gas prices, as well as the oil and natural gas production levels.

In February 2019, the Company announced that it intends to retire three aging coal-fired electric generating units, resulting from the Company's analysis showing that the plants are no longer expected to be cost competitive for customers. The retirements are expected to be in March 2021 for Unit 1 at Lewis & Clark Station in Sidney, Montana, and in early 2022 for Units 1 and 2 at Heskett Station near Mandan, North Dakota. In addition, the Company announced that it intends to construct Heskett Unit 4, an 88-MW simple-cycle natural gas-fired combustion turbine peaking unit at the existing Heskett Station near Mandan, North Dakota. Heskett Unit 4 production costs coupled with the MISO market purchases are expected to be about half the total cost of continuing to run the coal-fired electric generating units at Heskett and Lewis & Clark stations. Heskett Unit 4 was included in the Company's integrated resource plan submitted to the NDPSC in July 2019. On August 28, 2019, the Company filed for an advanced determination of prudence with the NDPSC for Heskett Unit 4. This request was approved by the NDPSC on August 5, 2020. Heskett Unit 4 is expected to be placed into service in 2023. The Company filed, and the commissions approved, requests with the NDPSC, MTPSC and SDPUC for the usage of deferred accounting for the costs related to the retirement of Unit 1 at Lewis & Clark Station and Units 1 and 2 at Heskett Station.

In December 2020, the governor of Washington outlined a climate policy package that included House Bill 1084, which would eliminate all onsite fossil fuel emissions in new buildings by 2030 and eliminate fossil fuels from existing buildings by 2050, among other things. A public hearing on House Bill 1084 was held February 17, 2021, in the House Committee on Appropriations. The Company is monitoring the status of the proposed legislation.

The Company continues to be focused on the regulatory recovery of its investments by filing for rate adjustments to seek recovery of operating costs and capital investments, as well as reasonable returns as allowed by regulators. The Company's most recent cases by jurisdiction are discussed in Item 8 - Note 20.

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Pipeline

Strategy and challenges The pipeline segment provides natural gas transportation, underground storage and energy-related services, as discussed in Items 1 and 2 - Business Properties. The segment focuses on utilizing its extensive expertise in the design, construction and operation of energy infrastructure and related services to increase market share and profitability through optimization of existing operations, organic growth and investments in energy-related assets within or in close proximity to its current operating areas. The segment focuses on the continual safety and reliability of its systems, which entails building, operating and maintaining safe natural gas pipelines and facilities. The segment continues to evaluate growth opportunities including the expansion of natural gas facilities; incremental pipeline projects; and expansion of energy-related services leveraging on its core competencies. In support of this strategy, the Company completed and placed into service the following organic growth projects in 2020 and 2019:

•In September 2020 and November 2019, Phase II and Phase I, respectively, of the Line Section 22 Expansion project in the Billings, Montana, area. The total project increased capacity by 22.5 MMcf per day.

•In February 2020, the Demicks Lake Expansion project in McKenzie County, North Dakota, increased capacity by 175 MMcf per day.

•In September 2019, the Demicks Lake project in McKenzie County, North Dakota, increased capacity by 175 MMcf per day.

The segment is exposed to energy price volatility which is impacted by the fluctuations in pricing, production and basis differentials of the energy market's commodities. Legislative and regulatory initiatives to increase pipeline safety regulations and reduce methane emissions could also impact the price and demand for natural gas.

The segment regularly experiences extended lead times on raw materials that are critical to the segment's construction and maintenance work. Long lead times on materials could delay maintenance work and project construction potentially causing lost revenues and/or increased costs. The Company continues to proactively monitor and plan for the material lead times, as well as work with manufacturers and suppliers to help mitigate the risk of delays due to extended lead times.

The pipeline segment is subject to extensive regulation including certain operational, environmental and system integrity regulations, as well as various permit terms and operational compliance conditions. In September 2019, the Pipeline and Hazardous Materials Safety Administration issued a rule for additional regulations to strengthen the safety of natural gas transmission and storage facilities and hazardous liquid pipelines. The segment has implemented procedure changes for the initial requirements and continues to evaluate procedure changes and implementation of physical modifications to existing facilities necessary for additional requirements effective July 1, 2021. The segment reviews and secures existing permits and easements, as well as new permits and easements as necessary, to meet current demand and future growth opportunities on an ongoing basis. Groups opposing pipelines could also cause negative impacts on the segment with increased costs, potential delays to project completion or cancellation of prospective projects.

The segment focuses on the recruitment and retention of a skilled workforce to remain competitive and provide services to its customers. The industry in which it operates relies on a skilled workforce to construct energy infrastructure and operate existing infrastructure in a safe manner. A shortage of skilled personnel can create a competitive labor market which could increase costs incurred by the segment. Competition from other pipeline companies can also have a negative impact on the segment.

Earnings overview - The following information summarizes the performance of the pipeline segment.

(Dollars in millions)

Operating expenses:

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Natural gas gathering volumes (MMdk) 8.6 13.9 14.9

Customer natural gas storage balance (MMdk):

Net injection (withdrawal) 9.3 2.3 (8.5)

2020 compared to 2019 Pipeline earnings increased $7.4 million as a result of:

Revenues: Increase of $3.5 million, largely attributable to increased transportation volumes and demand revenue of $6.2 million largely from organic growth projects, as previously discussed, and increased storage-related revenues of $4.6 million as a result of stronger demand for storage services. Also contributing to the increase was additional revenues of $2.4 million primarily from increased rates effective May 1, 2019, due to the FERC rate case finalized in September 2019. These increases were partially offset by lower non-regulated project revenues of $5.3 million and lower volumes associated with the sale of the Company's natural gas gathering assets in 2020, as discussed later, and lower gathering rates resulting in a decrease in revenues of $4.3 million.

Operation and maintenance: Decrease of $3.2 million, primarily from decreased non-regulated project costs of $3.7 million associated with lower non-regulated project revenue and $1.5 million gain on the sale of the Company's non-regulated natural gas gathering assets in 2020, as discussed later, partially offset by higher payroll-related costs.

Depreciation, depletion and amortization: Increase of $500,000, primarily due to additional expense of $1.3 million associated with increased property, plant and equipment balances as a result of organic growth projects that have been placed into service, and higher depreciation rates effective May 1, 2019, due to the FERC rate case finalized in September 2019. The sale of the Company's natural gas gathering assets in 2020, as discussed later, reduced the increases by $1.5 million.

Taxes, other than income: Decrease of $400,000 driven by the sale of the Company's natural gas gathering assets, partially offset by higher property taxes in certain jurisdictions of $300,000.

Other income: Increase of $1.7 million, as a result of higher AFUDC of $1.1 million, a positive impact of $700,000 related to the sale of the Company's regulated gathering assets and an out-of-period adjustment of $500,000 in the fourth quarter of 2020 related to previously overstated benefit plan expense, as discussed in Item 8 - Note 1. Partially offsetting these increases was the write-off of unrecovered gas costs and project expenses of $1.2 million.

Interest expense: Increase of $400,000, largely resulting from higher debt balances to finance organic growth projects, as previously discussed.

Income tax expense: Increase of $500,000, directly resulting from an increase in income before taxes, largely offset by the reversal of excess deferred taxes of $1.5 million associated with the sale of the Company's regulated natural gas gathering assets.

2019 compared to 2018 Pipeline earnings increased $1.1 million as a result of:

Revenues: Increase of $11.5 million, largely attributable to increased volumes of natural gas transported through its system as a result of organic growth projects, as previously discussed, and increased rates effective May 1, 2019, due to the FERC rate case finalized in September 2019.

Operation and maintenance: Increase of $900,000, primarily from higher payroll-related costs and materials costs.

Depreciation, depletion and amortization: Increase of $3.3 million, primarily due to increased property, plant and equipment balances, largely the result of organic growth projects that have been placed into service, and higher depreciation rates effective May 1, 2019, due to the FERC rate case finalized in September 2019.

Taxes, other than income: Increase of $600,000 driven by higher property taxes in certain jurisdictions.

Other income: Comparable to the prior year.

Interest expense: Increase of $1.3 million, largely resulting from higher debt balances to finance organic growth projects, as previously discussed.

Income tax expense: Increase of $4.5 million, primarily driven by the absence in 2019 of a $4.2 million income tax benefit recorded in 2018 related to the reversal of a regulatory liability recorded in 2017 based on a FERC final accounting order issued.

OutlookThe Company continues to successfully manage the impacts of the COVID-19 pandemic on its operations and is committed to providing safe, reliable and compliant service while ensuring the health and safety of its employees, customers and the communities in which it operates. The Company experienced minor delays on capital and maintenance projects during the first quarter of 2020 but resumed project activities in the second quarter of 2020. Work has progressed on these projects as scheduled through the fourth quarter of 2020. The Company does not expect delays to its regulatory filings due to the pandemic.

The Company has continued to experience the effect of associated natural gas production in the Bakken, which has provided opportunities for organic growth projects and increased demand. The completion of organic growth projects has contributed to the increased volumes of natural gas the Company transports through its system. Reduced global oil demand due to the COVID-19 pandemic and disagreements in oil supply levels between the Organization of the Petroleum Exporting Countries and other countries led to record low oil prices during the first quarter of 2020;

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however, oil prices started to recover after the first quarter of 2020 as states and other countries started to reopen. Although low oil prices have slowed drilling activities and led to the shut-in of certain wells, producers continue to bring wells back online and the Company continues to focus on growth and improving existing operations through organic projects in all areas in which it operates. The national record levels of natural gas supply over the last few years have moderated the need for storage services and put downward pressure on natural gas prices and minimized price volatility. While the Company believes there will continue to be varying pressures on natural gas production levels and prices due to these circumstances, low natural gas prices provide growth opportunity for industrial supply related projects and seasonal pricing differentials provide opportunities for storage services.

In January 2019, the Company announced the North Bakken Expansion project, which includes construction of a new pipeline, compression and ancillary facilities to transport natural gas from core Bakken production areas near Tioga, North Dakota, to a new connection with Northern Border Pipeline in McKenzie County, North Dakota. Construction is expected to begin in the second quarter of 2021 with an estimated in-service date late in 2021, which is dependent on regulatory and environmental permitting. On February 14, 2020, the Company filed with the FERC its application for this project. On July 28, 2020, the Company filed an amendment to its application with the FERC reflecting a decrease to the design capacity from 350 MMcf per day to 250 MMcf per day by reducing compression due to delays in forecasted growth levels of natural gas production in the Bakken region. Further, as a result of the forecasted Bakken oil and associated natural gas production delays driven by COVID-19 pandemic-related demand decreases and commodity price impacts, the Company negotiated adjustments to certain long-term customer commitments. A portion of the first-year committed volumes have been delayed one year and, through a combination of rate, volume and term adjustments, the overall project return profile remains unchanged and is expected to be accretive to earnings of the Company. These long-term take or pay customer contracts support the project at a design capacity of 250 MMcf per day, which can be readily expanded when forecasted growth levels rebound. On December 17, 2020, the FERC issued its environment assessment for the project. FERC approval of the project is anticipated in early 2021.

In December 2019, the Company entered into a purchase and sale agreement to divest of the Company's regulated natural gas gathering assets located in Montana and North Dakota, which included approximately 400 miles of natural gas gathering pipelines and associated compression and ancillary facilities. On January 8, 2020, the Company filed an application with the FERC to authorize abandonment by sale of the assets and received FERC approval on April 2, 2020. The sale closed in April 2020 with an effective date of January 1, 2020. Pursuant to the FERC's approval of the abandonment by sale, the proposed accounting treatment was filed with the FERC in October 2020 and approved in November 2020.

In October 2020, the Company entered into a purchase and sale agreement to divest of the Company's non-regulated natural gas gathering assets located in northern Montana, which included approximately 800 miles of natural gas gathering pipelines and associated compression and ancillary facilities. The sale closed in November 2020 with an effective date of December 1, 2020. With the completion of this sale, the Company has exited the natural gas gathering business.

Construction Materials and Contracting

Strategy and challengesThe construction materials and contracting segment provides an integrated set of aggregate-based construction services, as discussed in Items 1 and 2 - Business Properties. The segment focuses on high-growth strategic markets located near major transportation corridors and desirable mid-sized metropolitan areas; strengthening the long-term, strategic aggregate reserve position through available purchase and/or lease opportunities; enhancing profitability through cost containment, margin discipline and vertical integration of the segment's operations; development and recruitment of talented employees; and continued growth through organic and acquisition opportunities.

A key element of the Company's long-term strategy for this business is to further expand its market presence in the higher-margin materials business (rock, sand, gravel, liquid asphalt, asphalt concrete, ready-mixed concrete and related products), complementing and expanding on the segment's expertise. The Company's continued acquisition activity supports this strategy.

As one of the country's largest sand and gravel producers, the segment continues to strategically manage its approximately 1.1 billion tons of aggregate reserves in all its markets, as well as take further advantage of being vertically integrated. The segment's vertical integration allows the segment to manage operations from aggregate mining to final lay-down of concrete and asphalt, with control of and access to permitted aggregate reserves being significant. The Company's aggregate reserves are naturally declining and as a result, the Company seeks acquisition opportunities to replace the reserves. In the fourth quarter of 2020, the Company acquired the assets of McMurry Ready-Mix Co., an aggregates and concrete supplier located in Casper, Wyoming. The acquisition included nearly 100 million tons of aggregate reserves. In the first quarter of 2019, the Company purchased additional aggregate deposits in Texas that were estimated to contain a 40-year supply of high-quality aggregates for projected local market needs. Also during 2019, the Company increased aggregate reserves by approximately 40 million tons largely due to strategic asset purchases.

The construction materials and contracting segment faces challenges that are not under the direct control of the business. The segment operates in geographically diverse and highly competitive markets. Competition can put negative pressure on the segment's operating margins. The segment is also subject to volatility in the cost of raw materials such as diesel fuel, gasoline, liquid asphalt, cement and steel. Such volatility can have an impact on the segment's margins, including fixed-price construction contracts that are particularly vulnerable to the volatility of energy and material prices. Other variables that can impact the segment's margins include adverse weather conditions, the timing of project starts or completion and declines or delays in new and existing projects due to the cyclical nature of the construction industry and governmental infrastructure spending. Accordingly, operating results in any particular period may not be indicative of the results that can be expected for any other period.

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The segment also faces challenges in the recruitment and retention of employees. Trends in the labor market include an aging workforce and availability issues. The segment continues to face increasing pressure to control costs, as well as recruit and train a skilled workforce to meet the needs of increasing demand and seasonal work.

Earnings overview - The following information summarizes the performance of the construction materials and contracting segment.

(Dollars in millions)

Cost of sales:

Selling, general and administrative expense:

Depreciation, depletion and amortization 4.8 3.1 2.2 54.8 % 40.9 %

Total selling, general and administrative expense 99.6 94.0 84.1 6.0 % 11.8 %

2020 compared to 2019 Construction materials and contracting's earnings increased $26.9 million as a result of:

Revenues: Decrease of $12.7 million driven by lower contracting revenues partially due to lower materials pricing as a result of decreased energy-related costs. This decrease was offset in part by higher material sales on most product lines due to an early start to the season, favorable weather conditions in certain regions and additional revenues associated with the businesses acquired.

Gross margin: Increase of $40.1 million, largely resulting from higher material revenues and margins and higher contracting margins. Asphalt and asphalt-related product margins increased $21.3 million overall. Strong pricing for ready-mixed concrete in most markets resulted in 1.9 percent higher margins. Contracting bid margins positively impacted gross margin by $6.5 million partially resulting from lower direct costs associated with having a longer construction season due to favorable weather conditions. The Company also benefited across all product lines from lower fuel costs. Partially offsetting these increases was lower gains on asset sales in certain regions of approximately $6.8 million.

Selling, general and administrative expense: Increase of $5.6 million, primarily related to higher payroll-related costs of $2.2 million and increased amortization of intangible assets associated with the businesses acquired.

Other income: Decrease of $800,000, largely the result of an out-of-period adjustment to benefit expense in the fourth quarter of 2020, as discussed in Item 8 - Note 1.

Interest expense: Decrease of $3.2 million, from lower average debt balances in 2020 along with lower average interest rates.

Income tax expense: Increase of $10.0 million directly resulting from an increase in income before taxes.

2019 compared to 2018Construction materials and contracting's earnings increased $27.8 million as a result of:

Revenues: Increase of $264.8 million driven by higher contracting services and material sales due to strong economic environments in certain states, as well as additional material volumes associated with the businesses acquired.

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Gross margin: Increase of $48.5 million, largely resulting from higher revenues due to strong economic environments in certain states, as previously discussed, higher contracting bid margins and higher realized material prices. Also contributing to the increased gross margin was an increase in gains on asset sales in certain regions of approximately $7.5 million.

Selling, general and administrative expense: Increase of $9.9 million, primarily related to the businesses acquired and higher payroll-related costs.

Other income (expense): Increase of $4.7 million, largely the result of higher returns on the Company's benefit plan investments.

Interest expense: Increase of $6.5 million, largely resulting from higher debt balances as a result of recent acquisitions, capital expenditures and higher average interest rates.

Income tax expense: Increase of $9.0 million directly resulting from an increase in income before taxes.

OutlookThe Company continues to assess the impacts of the COVID-19 pandemic on its operations and is committed to the health and safety of its employees, customers and the communities in which it operates. The Company has implemented safety and social distancing measures for its employees that are not able to work from home and has experienced some inefficiencies and additional costs in relation to these measures but, for the most part, has been able to continue business processes with minimal interruptions. The Company also continues to monitor job progress and service work and at this time has not experienced significant delays, cancellations or disruptions due to the pandemic. The Company will continue to monitor the demand for construction materials and contracting services as such services may be reduced by recessionary impacts of the pandemic as the traditional customers for these services reduce capital expenditures. State and local mandates were issued in response to the COVID-19 pandemic requiring individuals to stay in place, leading to a reduction in fuel consumption in the United States, which directly reduces fuel tax collections. In addition, states, cities and counties across the country are experiencing low sales tax and other revenues as a result of the COVID-19 pandemic. The reduction in tax collections may impact funds available for public infrastructure projects, which in turn could have a material adverse impact on the Company's results of operations, financial position and cash flows. Meanwhile, a comprehensive infrastructure funding program, if adopted, by the United States Congress could positively impact the segment.

The segment's vertically integrated aggregate-based business model provides the Company with the ability to capture margin throughout the sales delivery process. The aggregate products are sold internally and externally for use in other products such as ready-mixed concrete, asphaltic concrete and public and private construction markets. The contracting services and construction materials are sold in connection with street, highway and other public infrastructure projects, as well as private commercial and residential development projects. The public infrastructure projects have traditionally been more stable markets as public funding is more secure during periods of economic decline. The public projects are, however, dependent on federal and state funding such as appropriations to the Federal Highway Administration. Spending on private development is highly dependent on both local and national economic cycles, providing additional sales during times of strong economic cycles.

During 2020 and 2019, the Company made strategic asset purchases and completed several acquisitions that support the Company's long-term strategy to expand its market presence. In the first quarter of 2020, the Company acquired the assets of Oldcastle Infrastructure Spokane, a prestressed-concrete business located in Spokane, Washington. In the fourth quarter of 2020, the Company acquired the assets of McMurry Ready-Mix Co., an aggregates and concrete supplier located in Casper, Wyoming. The Company continues to evaluate additional acquisition opportunities. For more information on the Company's business combinations, see Item 8 - Note 4.

The construction materials and contracting segment's backlog remained strong at December 31, 2020, at $673 million, which was comparable to backlog at December 31, 2019, of $693 million. A significant portion of the Company's backlog relates to street and highway construction. The Company expects to complete a significant amount of backlog at December 31, 2020, during the next 12 months.

Construction Services

Strategy and challenges The construction services segment provides inside and outside specialty contracting, as discussed in Items 1 and 2 - Business Properties. The construction services segment focuses on safely executing projects; providing a superior return on investment by building new and strengthening existing customer relationships; ensuring quality service; effectively controlling costs; retaining, developing and recruiting talented employees; growing through organic and acquisition opportunities; and focusing efforts on projects that will permit higher margins while properly managing risk. The growth experienced by the segment in recent years is due in part to its ability to support national customers in most of the regions in which it operates.

The construction services segment faces challenges in the highly competitive markets in which it operates. Competitive pricing environments, project delays, changes in management's estimates of variable consideration and the effects from restrictive regulatory requirements have negatively impacted revenues and margins in the past and could affect revenues and margins in the future. Additionally, margins may be negatively impacted on a quarterly basis due to adverse weather conditions, as well as timing of project starts or completions; disruptions to the supply chain due to transportation delays, travel restrictions, raw material cost increases and shortages and closures of businesses or facilities; declines or delays in new projects due to the cyclical nature of the construction industry; and other factors. These challenges may also impact the risk of loss on certain projects. Accordingly, operating results in any particular period may not be indicative of the results that can be expected for any other period.

The need to ensure available specialized labor resources for projects also drives strategic relationships with customers and project margins. These trends include an aging workforce and labor availability issues, increasing pressure to reduce costs and improve reliability, and increasing duration

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and complexity of customer capital programs. Due to these and other factors, the Company believes overall customer and competitor demand for labor resources will continue to increase, possibly surpassing the supply of industry resources.

Earnings overview - The following information summarizes the performance of the construction services segment.

(In millions)

Cost of sales:

Depreciation, depletion and amortization 15.7 15.0 14.3 4.7 % 4.9 %

Selling, general and administrative expense:

Depreciation, depletion and amortization 7.8 2.0 1.4 NM 42.9 %

* NM - not meaningful

2020 compared to 2019Construction services earnings increased $16.7 million as a result of:

Revenues: Increase of $246.4 million, primarily resulting from higher inside and outside specialty contracting workloads. Inside workloads contributed $127.2 million, or 10.0 percent more compared to 2019, largely from higher revenues of $71.4 million due to the addition of Perlectric, Inc. and increased customer demand for high-tech, hospitality and industrial projects. Outside workloads contributed $108.0 million, or 18.1 percent more compared to 2019, as a result of strong demand for utility projects including storm-related power line repair and wildfire restoration work.

Gross margin: Increase of $38.2 million, primarily from the higher volume of work resulting in an increase in revenues, as previously discussed, partially offset by an increase in operation and maintenance expense as a direct result of the expenses related to the increased workloads.

Selling, general and administrative expense: Increase of $17.0 million, largely from increased costs of $8.3 million associated with the addition of PerLectric, Inc. operations, allowance for uncollectible accounts of $3.6 million, payroll-related costs of $3.1 million and office expenses.

Other income: Comparable to the prior year.

Interest expense: Decrease of $1.2 million, related to lower debt balances due to lower working capital needs as a result of payroll tax deferrals and increased cash collections.

Income tax expense: Increase of $5.8 million, directly resulting from an increase in income before taxes.

2019 compared to 2018 Construction services earnings increased $28.7 million as a result of:

Revenues: Increase of $477.8 million, largely resulting from higher inside specialty contracting workloads from an increase in customer demand for hospitality, data center and high-tech projects. Also contributing to the increase was higher outside specialty contracting workloads, primarily resulting from increased utility customer demand.

Gross margin: Increase of $55.3 million, primarily due to the higher volume of work resulting in an increase in revenues, as previously discussed, partially offset by an increase in operation and maintenance expense as a direct result of the increased workloads.

Selling, general and administrative expense: Increase of $15.7 million, resulting from increased payroll-related costs, as well as higher office expense and outside professional service costs.

Other income: Increase of $800,000, largely resulting from higher returns on the Company's benefit plan investments.

Interest expense: Increase of $1.7 million, related to higher debt balances as a result of additional working capital needs from the increase in contracting workloads in 2019.

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Income tax expense: Increase of $10.0 million, directly resulting from an increase in income before taxes.

The Company continues to have bidding opportunities for both inside and outside specialty contracting work in 2021. Although bidding remains highly competitive in all areas, the Company expects the segment's skilled workforce, quality of service and effective cost management will continue to provide a benefit in securing and executing profitable projects.

The construction services segment's backlog at December 31 was as follows:

(In millions)

Inside specialty contracting $ 1,059 $ 908

Outside specialty contracting 214 236

The increase in backlog at December 31, 2020, as compared to backlog at December 31, 2019, was largely attributable to the new project opportunities that the Company continues to be awarded across its diverse operations, particularly inside specialty electrical and mechanical contracting in the hospitality, high-tech and public industries. The Company's outside power, communications and natural gas specialty contracting also have a high volume of available work. The Company expects to complete a significant amount of the backlog at December 31, 2020, during the next 12 months. Additionally, the Company continues to further evaluate potential acquisition opportunities that would be accretive to earnings of the Company and continue to grow the Company's backlog.

In support of the Company's strategic plan to grow through acquisitions, the Company acquired PerLectric, Inc., an electrical construction company in Fairfax, Virginia, in the first quarter of 2020. For more information on the Company's business combinations, see Item 8 - Note 4.

Other

(In millions)

Operating expenses:

Depreciation, depletion and amortization 2.7 2.1 2.0 28.6 % 5.0 %

Taxes, other than income .1 .1 .1 — % — %

Income tax benefit (.4) (.1) (1.2) NM 91.7 %

Net loss $ (3.1) $ (2.1) $ (.7) (47.6) % NM

* NM - not meaningful

Included in Other is insurance activity at the Company's captive insurer and general and administrative costs and interest expense previously allocated to the exploration and production and refining businesses that do not meet the criteria for income (loss) from discontinued operations.

Other was negatively impacted in 2020 as a result of higher insurance claims as compared to 2019, whereas 2019 had higher insurance premiums which increased both operating revenues and operation and maintenance expense.

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Intersegment Transactions

Amounts presented in the preceding tables will not agree with the Consolidated Statements of Income due to the Company's elimination of intersegment transactions. The amounts related to these items were as follows:

(In millions)

Intersegment transactions:

For more information on intersegment eliminations, see Item 8 - Note 17.

Liquidity and Capital Commitments

At December 31, 2020, the Company had cash and cash equivalents of $59.6 million and available borrowing capacity of $736.3 million under the outstanding credit facilities of the Company's subsidiaries. During the first quarter of 2020, short-term capital markets were disrupted as a result of the COVID-19 pandemic. Consequently, the Company temporarily borrowed under its revolving credit agreements in addition to accessing the commercial paper markets and maintained higher than normal cash balances to ensure liquidity during this volatile period. At December 31, 2020, all borrowings under the revolving credit agreements for Montana-Dakota and Centennial had been repaid. The Company expects to meet its obligations for debt maturing within 12 months and its other operating and capital requirements from various sources, including internally generated funds; credit facilities and commercial paper of the Company's subsidiaries, as described later in Capital resources; and the issuance of debt and equity securities if necessary.

Cash flows

Operating activities The changes in cash flows from operating activities generally follow the results of operations as discussed in Business Segment Financial and Operating Data and are also affected by changes in working capital. Changes in cash flows for discontinued operations are related to the Company's former exploration and production and refining businesses.

Cash flows provided by operating activities in 2020 was $768.4 million compared to $542.3 million in 2019. The increase in cash flows provided by operating activities is reflective of the increased earnings across all businesses. The increase in cash flows provided by operating activities was largely driven by stronger collection of accounts receivable at the construction services business and decreased receivables at the construction materials and contracting business as compared to the prior period as a result of lower contracting revenues. Also contributing to the increase in cash flows provided by operating activities was the decrease in natural gas purchases in 2020 as a result of milder temperatures and lower gas costs and recovery of purchased gas cost adjustment balances at the natural gas distribution business. The Company also benefited from the deferral of payroll taxes related to the CARES Act and the absence of pension contributions at all of its businesses. Partially offsetting these increases was higher cash needs due to decreased bonus depreciation for tax purposes taken on qualified property in 2020 as compared to 2019 and a decrease in deferred taxes as a result of the purchased gas cost adjustment recorded in 2019.

Cash flows provided by operating activities in 2019 were $542.3 million compared to $499.9 million in 2018. The increase in cash flows provided by operating activities was largely driven by increased earnings from higher workloads at the construction businesses, which were partially offset by an increase in accounts receivable as a result of the higher workloads. Lower inventory balances due to higher workloads at the construction materials and contracting business in 2019 as compared to the increase in inventory balances in 2018 due to the activity of acquired businesses also contributed to the increase. Partially offsetting these increases were higher natural gas purchases including the effects of colder weather, higher gas costs and timing of collection of such balances from customers at the natural gas distribution business, as well as higher pension contributions at all of the businesses.

Investing activities Cash flows used in investing activities in 2020 were $630.2 million compared to $603.9 million in 2019. The increase in cash used was primarily related to additional cash needs for acquisition activity in 2020 compared to 2019 at the construction businesses, increased capital expenditures in 2020 at the electric business and lower proceeds on asset sales in 2020 at the construction materials and contracting business. Partially offsetting these increases were decreased capital expenditures in 2020 at the construction materials and contracting business, proceeds on the natural gas gathering asset sales at the pipeline business and higher proceeds on asset sales in 2020 at the construction services businesses.

Cash flows used in investing activities in 2019 was $603.9 million compared to $710.9 million in 2018. The decrease in cash used was primarily related to $112.1 million lower cash used in acquisition activity in 2019 compared to 2018 at the construction materials and contracting business and higher proceeds on asset sales at the construction businesses in 2019.

Financing activitiesCash flows used in financing activities in 2020 was $145.1 million compared to cash flows provided by financing activities of $74.1 million in 2019. The change was largely the result of a decrease in net long-term and short-term debt borrowings in 2020 as compared to

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2019 due to lower working capital needs. In addition, the Company had decreased net proceeds of $103.5 million in 2020 due to the absence of common stock issuance under its "at-the-market" offering and 401(k) plan.

Cash flows provided by financing activities in 2019 were $74.1 million compared to $230.4 million in 2018. The decrease in cash provided by financing activities was largely due to the higher repayment of long-term debt in 2019 on debt issued in 2018 for acquisitions at the construction materials and contracting business. The Company also borrowed and repaid short-term borrowings in 2019. Partially offsetting the decrease in cash provided by financing activities was the receipt of proceeds from the issuance of common stock. The Company issued common stock for net proceeds of $106.8 million under its "at-the-market" offering and 401(k) plan in 2019.

Defined benefit pension plans

The Company has noncontributory qualified defined benefit pension plans for certain employees. Plan assets consist of investments in equity and fixed-income securities. Various actuarial assumptions are used in calculating the benefit expense (income) and liability (asset) related to the pension plans. Actuarial assumptions include assumptions about the discount rate and expected return on plan assets. At December 31, 2020, the pension plans' accumulated benefit obligations exceeded these plans' assets by approximately $53.5 million. Pretax pension income reflected in the Consolidated Statements of Income for the year ended December 31, 2020, was $684,000. Pretax pension expense reflected in the Consolidated Statements of Income for the years ended December 31, 2019 and 2018, was $2.5 million and $843,000, respectively. The Company's pension income is currently projected to be approximately $1.7 million in 2021. Funding for the pension plans is actuarially determined. The Company has no minimum funding requirements for its defined benefit pension plans for 2021 due to an additional contribution of $20.0 million in 2019. There were no minimum required contributions for the year ended December 31, 2020, and the minimum required contributions for the years ended December 31, 2019 and 2018, were approximately $4.9 million and $6.1 million, respectively. For more information on the Company's pension plans, see Item 8 - Note 18.

Capital expenditures

The Company's capital expenditures for 2018 through 2020 and as anticipated for 2021 through 2023 are summarized in the following table.

Actual* Estimated

(In millions)

Capital expenditures:

* Capital expenditures for 2020, 2019 and 2018 include noncash transactions such as the issuance of the Company's equity securities in connection with acquisitions, capital expenditure-related accounts payable, AFUDC and accrual of holdback payments in connection with acquisitions totaling $(15.7) million, $4.8 million and $33.4 million, respectively.

The 2020 capital expenditures include the completed business combinations at the construction materials and contracting and construction services segments, as discussed in Item 8 - Note 4. The 2020 capital expenditures were funded by internal sources and borrowings under credit facilities and issuance of commercial paper of the Company's subsidiaries. The Company has included in the estimated capital expenditures for 2021 through 2023 the North Bakken Expansion project and construction of Heskett Unit 4, as previously discussed in Business Segment Financial and Operating Data.

Estimated capital expenditures for the years 2021 through 2023 include those for:

•System upgrades

•Routine replacements

•Service extensions

•Routine equipment maintenance and replacements

•Buildings, land and building improvements

•Pipeline and natural gas storage projects

•Power generation and transmission opportunities

•Environmental upgrades

•Other growth opportunities

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The Company continues to evaluate potential future acquisitions and other growth opportunities that would be incremental to the outlined capital program; however, they are dependent upon the availability of economic opportunities and, as a result, capital expenditures may vary significantly from the estimates in the preceding table. It is anticipated that all of the funds required for capital expenditures for the years 2021 through 2023 will be funded by various sources, including internally generated funds; credit facilities and commercial paper of the Company's subsidiaries, as described later; and issuance of debt and equity securities if necessary.

Capital resources

Certain debt instruments of the Company's subsidiaries, including those discussed later, contain restrictive and financial covenants and cross-default provisions. In order to borrow under the debt agreements, the subsidiary companies must be in compliance with the applicable covenants and certain other conditions, all of which the subsidiaries, as applicable, were in compliance with at December 31, 2020. In the event the subsidiaries do not comply with the applicable covenants and other conditions, alternative sources of funding may need to be pursued. For more information on the covenants, certain other conditions and cross-default provisions, see Item 8 - Note 9.

The following table summarizes the outstanding revolving credit facilities of the Company's subsidiaries at December 31, 2020:

(In millions)

(a) The commercial paper program is supported by a revolving credit agreement with various banks (provisions allow for increased borrowings, at the option of Montana-Dakota on stated conditions, up to a maximum of $225.0 million). There were no amounts outstanding under the revolving credit agreement.

(b) Certain provisions allow for increased borrowings, up to a maximum of $125.0 million.

(d) Certain provisions allow for increased borrowings, up to a maximum of $110.0 million.

(e) The commercial paper program is supported by a revolving credit agreement with various banks (provisions allow for increased borrowings, at the option of Centennial on stated conditions, up to a maximum of $700.0 million). There were no amounts outstanding under the revolving credit agreement.

The respective commercial paper programs are supported by revolving credit agreements. While the amount of commercial paper outstanding does not reduce available capacity under the respective revolving credit agreements, Montana-Dakota and Centennial do not issue commercial paper in an aggregate amount exceeding the available capacity under their credit agreements. The commercial paper borrowings may vary during the period, largely the result of fluctuations in working capital requirements due to the seasonality of certain operations of the Company's subsidiaries.

Total equity as a percent of total capitalization was 58 percent and 56 percent at December 31, 2020 and 2019, respectively. This ratio is calculated as the Company's total equity, divided by the Company's total capital. Total capital is the Company's total debt, including short-term borrowings and long-term debt due within 12 months, plus total equity. This ratio is an indicator of how the Company is financing its operations, as well as its financial strength. As of December 31, 2020, the Company had investment grade credit ratings at all entities issuing debt.

The Company currently has a shelf registration statement on file with the SEC, under which the Company may issue and sell any combination of common stock and debt securities. The Company may sell such securities if warranted by market conditions and the Company's capital requirements. Any public offer and sale of such securities will be made only by means of a prospectus meeting the requirements of the Securities Act and the rules and regulations thereunder.

In August 2020, the Company amended the Distribution Agreement dated February 22, 2019, with J.P. Morgan Securities LLC and MUFG Securities Americas Inc., as sales agents. The Distribution Agreement allows the offering, issuance and sale of up to 6.4 million shares of the Company's common stock in connection with an “at-the-market” offering. The common stock may be offered for sale, from time to time, in accordance with the terms and conditions of the agreement. Proceeds from the sale of shares of common stock under the agreement have been and are expected to be used for general corporate purposes, which may include, among other things, working capital, capital expenditures, debt repayment and the financing of acquisitions.

The Company did not issue any shares of common stock for the year ended December 31, 2020, pursuant to the “at-the-market” offering. As of December 31, 2020, the Company had capacity to issue up to 6.4 million additional shares of common stock under the "at-the-market" offering program. For more information on the Company's "at-the-market" offering, see Item 8 - Note 12.

Certain of the Company's debt instruments use LIBOR as a benchmark for establishing the applicable interest rate. LIBOR is the subject of recent national, international and other regulatory guidance and proposals for reform. These reforms and other pressures may cause LIBOR to disappear entirely or to perform differently than in the past. The Company has been proactive to anticipate the reform of LIBOR by replacing it with SOFR in certain of its new debt instruments, as well as those that are being renewed. The Company continues to evaluate the impact the reform will have on its debt instruments and, at this time, does not anticipate a significant impact.

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The following includes information related to the preceding table.

Montana-Dakota On January 1, 2019, the Company's revolving credit agreement and commercial paper program became Montana-Dakota's revolving credit agreement and commercial paper program as a result of the Holding Company Reorganization. The outstanding balance of the revolving credit agreement was also transferred to Montana-Dakota. All of the related terms and covenants of the credit agreements remained the same.

On December 19, 2019, Montana-Dakota amended and restated its revolving credit agreement extending the maturity date to December 19, 2024. Montana-Dakota's revolving credit agreement supports its commercial paper program. Commercial paper borrowings under this agreement are classified as long-term debt as they are intended to be refinanced on a long-term basis through continued commercial paper borrowings. Montana-Dakota's objective is to maintain acceptable credit ratings in order to access the capital markets through the issuance of commercial paper. Historically, downgrades in credit ratings have not limited, nor are currently expected to limit, Montana-Dakota's ability to access the capital markets. If Montana-Dakota were to experience a downgrade of its credit ratings in the future, it may need to borrow under its credit agreement and may experience an increase in overall interest rates with respect to its cost of borrowings. Prior to the maturity of the credit agreement, Montana-Dakota expects that it will negotiate the extension or replacement of this agreement. If Montana-Dakota is unable to successfully negotiate an extension of, or replacement for, the credit agreement, or if the fees on this facility become too expensive, which Montana-Dakota does not currently anticipate, it would seek alternative funding.

On April 8, 2020, Montana-Dakota entered into a $75.0 million term loan agreement with a LIBOR-based variable interest rate and a maturity date of April 7, 2021. At December 31, 2020, Montana-Dakota had $50.0 million outstanding under this agreement. On February 16, 2021, Montana-Dakota repaid the remaining $50.0 million outstanding.

Cascade On June 7, 2019, Cascade amended its revolving credit agreement to increase the borrowing limit to $100.0 million and extend the maturity date to June 7, 2024. Any borrowings under the revolving credit agreement are classified as long-term debt as they are intended to be refinanced on a long-term basis through continued borrowings.

On June 15, 2020, Cascade issued $50.0 million of senior notes under a note purchase agreement with maturity dates ranging from June 15, 2050 to June 15, 2060, at a weighted average interest rate of 3.66 percent.

On October 30, 2020, Cascade issued $25.0 million of senior notes under a note purchase agreement with a maturity date of October 30, 2060, at an interest rate of 3.34 percent.

Intermountain On June 7, 2019, Intermountain amended its revolving credit agreement to extend the maturity date to June 7, 2024. Any borrowings under the revolving credit agreement are classified as long-term debt as they are intended to be refinanced on a long-term basis through continued borrowings.

Centennial On December 19, 2019, Centennial amended and restated its revolving credit agreement to increase the borrowing capacity to $600.0 million and extend the maturity date to December 19, 2024. Centennial's revolving credit agreement supports its commercial paper program. Commercial paper borrowings under this agreement are classified as long-term debt as they are intended to be refinanced on a long-term basis through continued commercial paper borrowings. Centennial's objective is to maintain acceptable credit ratings in order to access the capital markets through the issuance of commercial paper. Historically, downgrades in Centennial's credit ratings have not limited, nor are currently expected to limit, Centennial's ability to access the capital markets. If Centennial were to experience a downgrade of its credit ratings in the future, it may need to borrow under its credit agreement and may experience an increase in overall interest rates with respect to its cost of borrowings. Prior to the maturity of the Centennial credit agreement, Centennial expects that it will negotiate the extension or replacement of this agreement, which provides credit support to access the capital markets. In the event Centennial is unable to successfully negotiate this agreement, or in the event the fees on this facility become too expensive, which Centennial does not currently anticipate, it would seek alternative funding.

WBI Energy Transmission On July 26, 2019, WBI Energy Transmission amended its uncommitted note purchase and private shelf agreement to increase capacity to $300.0 million and extend the issuance period and expiration date to May 16, 2022. On December 16, 2020, WBI Energy Transmission issued $25.0 million of senior notes under the private shelf agreement with a maturity date of December 16, 2035, at an interest rate of 3.26 percent. WBI Energy Transmission had $195.0 million of notes outstanding at December 31, 2020, which reduced the remaining capacity under this uncommitted private shelf agreement to $105.0 million.

Dividend restrictions

For information on the Company's dividends and dividend restrictions, see Item 8 - Note 12.

Off balance sheet arrangements

As of December 31, 2020, the Company had no material off balance sheet arrangements as defined by the rules of the SEC.

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Contractual obligations and commercial commitments

For more information on the Company's contractual obligations on long-term debt, operating leases and purchase commitments, see

Item 8 - Notes 9, 10 and 21. At December 31, 2020, the Company's commitments under these obligations were as follows:

Less than 1 year 1-3 years 3-5 years More than 5 years Total

(In millions)

* Unamortized debt issuance costs and discount are excluded from the table.

** Represents the estimated interest payments associated with the Company's long-term debt outstanding at December 31, 2020, assuming current interest rates and consistent amounts outstanding until their respective maturity dates over the periods indicated in the table above.

At December 31, 2020, the Company had total liabilities of $446.9 million related to asset retirement obligations that are excluded from the table above. Of the total asset retirement obligations, the current portion was $6.6 million at December 31, 2020, and was included in other accrued liabilities on the Consolidated Balance Sheets. Due to the nature of these obligations, the Company cannot determine precisely when the payments will be made to settle these obligations. For more information, see Item 8 - Note 11.

Not reflected in the previous table are $1.3 million in uncertain tax positions at December 31, 2020.

The Company has no minimum funding requirements for its defined benefit pension plans for 2021 due to an additional contribution of $20.0 million in 2019.

The Company's MEPP contributions are based on union employee payroll, which cannot be determined in advance for future periods. The Company may also be required to make additional contributions to its MEPPs as a result of their funded status. For more information, see Item 1A - Risk Factors and Item 8 - Note 18.

New Accounting Standards

For information regarding new accounting standards, see Item 8 - Note 2, which is incorporated herein by reference.

Critical Accounting Estimates

The Company has prepared its financial statements in conformity with GAAP. The preparation of its financial statements requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the financial statements, as well as the reported amounts of revenues and expenses during the reporting period. Management reviews these estimates and assumptions based on historical experience, changes in business conditions and other relevant factors believed to be reasonable under the circumstances.

Critical accounting estimates are defined as estimates that require management to make assumptions about matters that are uncertain at the time the estimate was made and changes in the estimates could have a material impact on the Company's financial position or results of operations. The Company's critical accounting estimates are subject to judgments and uncertainties that affect the application of its significant accounting policies discussed in Item 8 - Note 2. As additional information becomes available, or actual amounts are determinable, the recorded estimates are revised. Consequently, the Company's financial position or results of operations may be materially different when reported under different conditions or when using different assumptions in the application of the following critical accounting estimates.

Goodwill

The Company performs its goodwill impairment testing annually in the fourth quarter. In addition, the test is performed on an interim basis whenever events or circumstances indicate that the carrying amount of goodwill may not be recoverable. Examples of such events or circumstances may include a significant adverse change in business climate, weakness in an industry in which the Company's reporting units operate or recent significant cash or operating losses with expectations that those losses will continue.

The Company has determined that the reporting units for its goodwill impairment test are its operating segments, or components of an operating segment, that constitute a business for which discrete financial information is available and for which segment management regularly reviews the operating results. For more information on the Company's operating segments, see Item 8 - Note 17. Goodwill impairment, if any, is measured by comparing the fair value of each reporting unit to its carrying value. If the fair value of a reporting unit exceeds its carrying value, the goodwill of the reporting unit is not impaired. If the carrying value of a reporting unit exceeds its fair value, the Company must record an impairment loss for the

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amount that the carrying value of the reporting unit, including goodwill, exceeds the fair value of the reporting unit. For the years ended December 31, 2020, 2019 and 2018, there were no impairment losses recorded. At October 31, 2020, the fair value substantially exceeded the carrying value at all reporting units.

Determining the fair value of a reporting unit requires judgment and the use of significant estimates which include assumptions about the Company's future revenue, profitability and cash flows, amount and timing of estimated capital expenditures, inflation rates, risk adjusted capital cost, operational plans, and current and future economic conditions, among others. The fair value of each reporting unit is determined using a weighted combination of income and market approaches. The Company uses a discounted cash flow methodology for its income approach. Under the income approach, the discounted cash flow model determines fair value based on the present value of projected cash flows over a specified period and a residual value related to future cash flows beyond the projection period. Both values are discounted using a rate which reflects the best estimate of the risk adjusted capital cost at each reporting unit. Risk adjusted capital cost, which varies by reporting unit and was in the range of 4 percent to 8 percent, was utilized in the goodwill impairment test performed in the fourth quarter of 2020. The goodwill impairment test also utilized a long-term growth rate projection, which varies by reporting unit and was in the range of approximately 1 percent to 3 percent, in the goodwill impairment test performed in the fourth quarter of 2020. Under the market approach, the Company estimates fair value using various multiples derived from enterprise value to EBITDA for comparative peer companies for each respective reporting unit. These multiples are applied to operating data for each reporting unit to arrive at an indication of fair value. In addition, the Company adds a reasonable control premium when calculating the fair value utilizing the peer multiples, which is estimated as the premium that would be received in a sale in an orderly transaction between market participants. The Company believes that the estimates and assumptions used in its impairment assessments are reasonable and based on available market information.

Business combinations

The Company accounts for acquisitions on the Consolidated Financial Statements starting from the date of the acquisition, which is the date that control is obtained. The acquisition method of accounting requires acquired assets and liabilities assumed be recorded at their respective fair values as of the date of the acquisition. The excess of the purchase price over the fair value of the assets acquired and liabilities assumed is recorded as goodwill. The estimation of fair values of acquired assets and liabilities assumed by the Company requires significant judgment and requires various assumptions. Although independent appraisals may be used to assist in the determination of the fair value of certain assets and liabilities, the appraised values may be based on significant estimates provided by management. The amounts and useful lives assigned to depreciable and amortizable assets compared to amounts assigned to goodwill, which is not amortized, can affect the results of operations in the period of and periods subsequent to a business combination.

In determining fair values of acquired assets and liabilities assumed, the Company uses various observable inputs for similar assets or liabilities in active markets and various unobservable inputs, which includes the use of valuation models. Fair values are based on various factors including, but not limited to, age and condition of property, maintenance records, auction values for equipment with similar characteristics, recent sales and listings of comparable properties, data collected from drill holes and other subsurface investigations and geologic data. The Company primarily uses the market and cost approaches in determining the fair value of land and property, plant and equipment. A combination of the market and income approaches are used for aggregate reserves and intangibles, primarily a discounted cash flow model.

There is a measurement period after the acquisition date during which the Company may adjust the amounts recognized for a business combination. Any such adjustments are recorded in the period the adjustment is determined with the corresponding offset to goodwill. These adjustments are typically based on obtaining additional information that existed at the acquisition date regarding the assets acquired and the liabilities assumed. The measurement period ends once the Company has obtained all necessary information that existed as of the acquisition date, but does not extend beyond one year from the date of the acquisition. Once the measurement period has ended, any adjustments to assets acquired or liabilities assumed are recorded in income from continuing operations.

Regulatory accounting

The Company is subject to rate regulation by state public service commissions and/or the FERC. The Company's regulated businesses account for certain income and expense items under the provisions of regulatory accounting, which require these businesses to defer as regulatory assets or liabilities certain items that would have otherwise been reflected as expense or income, respectively, based on the expected regulatory treatment in future rates. Regulatory assets generally represent incurred or accrued costs that have been deferred and are expected to be recovered in rates charged to customers. Regulatory liabilities generally represent amounts that are expected to be refunded to customers in future rates or amounts collected in current rates for future costs.

Management continually assesses the likelihood of recovery in future rates of incurred costs and refunds to customers associated with regulatory assets and liabilities. Decisions made by the various regulatory agencies can directly impact the amount and timing of these items. Therefore, expected recovery or flowback of these deferred items generally is based on specific ratemaking decisions or precedent for each item. If future recovery of costs is no longer probable, the Company would be required to include those costs in the statement of income or accumulated other comprehensive income (loss) in the period in which it is no longer deemed probable. The Company believes that the accounting subject to rate regulation remains appropriate and its regulatory assets are probable of recovery in current rates or in future rate proceedings. At December 31, 2020 and 2019, the Company's regulatory assets were $447.9 million and $417.4 million, respectively, and regulatory liabilities were $459.5 million and $490.3 million, respectively.

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Revenue recognition

Revenue is recognized to depict the transfer of promised goods or services to customers in an amount that reflects the consideration to which the entity expects to be entitled in exchange for those goods or services. The recognition of revenue requires the Company to make estimates and assumptions that affect the reported amounts of revenue. The accuracy of revenues reported on the Consolidated Financial Statements depends on, among other things, management's estimates of total costs to complete projects because the Company uses the cost-to-cost measure of progress on construction contracts for revenue recognition.

To determine the proper revenue recognition method for contracts, the Company evaluates whether two or more contracts should be combined and accounted for as one single contract and whether the combined or single contract should be accounted for as more than one performance obligation. This evaluation requires significant judgment and the decision to combine a group of contracts or separate the combined or single contract into multiple performance obligations could change the amount of revenue and profit recorded in a given period. For most contracts, the customer contracts with the Company to provide a significant service of integrating a complex set of tasks and components into a single project. Hence, the Company's contracts are generally accounted for as one performance obligation.

The Company recognizes construction contract revenue over time using an input method based on the cost-to-cost measure of progress for contracts because it best depicts the transfer of assets to the customer which occurs as the Company incurs costs on the contract. Under the cost-to-cost measure of progress, the costs incurred are compared with total estimated costs of a performance obligation. Revenues are recorded proportionately to the costs incurred. This method depends largely on the ability to make reasonably dependable estimates related to the extent of progress toward completion of the contract, contract revenues and contract costs. Inasmuch as contract prices are generally set before the work is performed, the estimates pertaining to every project could contain significant unknown risks such as volatile labor, material and fuel costs, weather delays, adverse project site conditions, unforeseen actions by regulatory agencies, performance by subcontractors, job management and relations with project owners. Changes in estimates could have a material effect on the Company's results of operations, financial position and cash flows. For the years ended December 31, 2020 and 2019, the Company's total construction contract revenue was $3.1 billion and $2.8 billion, respectively.

Several factors are evaluated in determining the bid price for contract work. These include, but are not limited to, the complexities of the job, past history performing similar types of work, seasonal weather patterns, competition and market conditions, job site conditions, work force safety, reputation of the project owner, availability of labor, materials and fuel, project location and project completion dates. As a project commences, estimates are continually monitored and revised as information becomes available and actual costs and conditions surrounding the job become known. If a loss is anticipated on a contract, the loss is immediately recognized.

Contracts are often modified to account for changes in contract specifications and requirements. The Company considers contract modifications to exist when the modification either creates new or changes the existing enforceable rights and obligations. Generally, contract modifications are for goods or services that are not distinct from the existing contract due to the significant integration of services provided in the context of the contract and are accounted for as if they were part of that existing contract. The effect of a contract modification on the transaction price and the measure of progress for the performance obligation to which it relates, is recognized as an adjustment to revenue on a cumulative catch-up basis.

The Company's construction contracts generally contain variable consideration including liquidated damages, performance bonuses or incentives, claims, unapproved/unpriced change orders and penalties or index pricing. The variable amounts usually arise upon achievement of certain performance metrics or change in project scope. The Company estimates the amount of revenue to be recognized on variable consideration using estimation methods that best predict the most likely amount of consideration the Company expects to be entitled to or expects to incur. The Company includes variable consideration in the estimated transaction price to the extent it is probable that a significant reversal of cumulative revenue recognized will not occur or when the uncertainty associated with the variable consideration is resolved. Changes in circumstances could impact management's estimates made in determining the value of variable consideration recorded. The Company updates its estimate of the transaction price each reporting period and the effect of variable consideration on the transaction price is recognized as an adjustment to revenue on a cumulative catch-up basis.

The Company believes its estimates surrounding the cost-to-cost method are reasonable based on the information that is known when the estimates are made. The Company has contract administration, accounting and management control systems in place that allow its estimates to be updated and monitored on a regular basis. Because of the many factors that are evaluated in determining bid prices, it is inherent that the Company's estimates have changed in the past and will continually change in the future as new information becomes available for each job.

Pension and other postretirement benefits

The Company has noncontributory defined benefit pension plans and other postretirement benefit plans for certain eligible employees. Various actuarial assumptions are used in calculating the benefit expense (income) and liability (asset) related to these plans. Costs of providing pension and other postretirement benefits bear the risk of change, as they are dependent upon numerous factors based on assumptions of future conditions.

The Company makes various assumptions when determining plan costs, including the current discount rates and the expected long-term return on plan assets, the rate of compensation increases, actuarially determined mortality data and health care cost trend rates. In selecting the expected long-term return on plan assets, which is considered to be one of the key variables in determining benefit expense or income, the Company considers historical returns, current market conditions, the mix of investments and expected future market trends, including changes in interest rates and

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equity and bond market performance. Another key variable in determining benefit expense or income is the discount rate. In selecting the discount rate, the Company matches forecasted future cash flows of the pension and postretirement plans to a yield curve which consists of a hypothetical portfolio of high-quality corporate bonds with varying maturity dates, as well as other factors, as a basis. The Company's pension and other postretirement benefit plan assets are primarily made up of equity and fixed-income investments. Fluctuations in actual equity and bond market returns, as well as changes in general interest rates, may result in increased or decreased pension and other postretirement benefit costs in the future. Management estimates the rate of compensation increase based on long-term assumed wage increases and the health care cost trend rates are determined by historical and future trends. The Company estimates that a 50-basis point decrease in the discount rate or in the expected return on plan assets would each increase expense by approximately $2.0 million (after-tax) for the year ended December 31, 2020.

The Company believes the estimates made for its pension and other postretirement benefits are reasonable based on the information that is known when the estimates are made. These estimates and assumptions are subject to a number of variables and are expected to change in the future. Estimates and assumptions will be affected by changes in the discount rate, the expected long-term return on plan assets, the rate of compensation increase and health care cost trend rates. The Company plans to continue to use its current methodologies to determine plan costs. For more information on the assumptions used in determining plan costs, see Item 8 - Note 18.

Income taxes

The Company is required to make judgments regarding the potential tax effects of various financial transactions and ongoing operations to estimate the Company's obligation to taxing authorities. These tax obligations include income, real estate, franchise and sales/use taxes. Judgments related to income taxes require the recognition in the Company's financial statements that a tax position is more-likely-than-not to be sustained on audit.

Judgment and estimation is required in developing the provision for income taxes and the reporting of tax-related assets and liabilities and, if necessary, any valuation allowances. The interpretation of tax laws can involve uncertainty, since tax authorities may interpret such laws differently. Actual income tax could vary from estimated amounts and may result in favorable or unfavorable impacts to net income, cash flows and tax-related assets and liabilities. In addition, the effective tax rate may be affected by other changes including the allocation of property, payroll and revenues between states.

The Company assesses the deferred tax assets for recoverability taking into consideration historical and anticipated earnings levels; the reversal of other existing temporary differences; available net operating losses and tax carryforwards; and available tax planning strategies that could be implemented to realize the deferred tax assets. Based on this assessment, management must evaluate the need for, and amount of, a valuation allowance against the deferred tax assets. As facts and circumstances change, adjustment to the valuation allowance may be required.

Non-GAAP Financial Measures

The Business Segment Financial and Operating Data includes financial information prepared in accordance with GAAP, as well as another financial measure, adjusted gross margin, that is considered a non-GAAP financial measure as it relates to the Company's electric and natural gas distribution segments. The presentation of adjusted gross margin is intended to be a useful supplemental financial measure for investors’ understanding of the segments' operating performance. This non-GAAP financial measure should not be considered as an alternative to, or more meaningful than, GAAP financial measures such as operating income (loss) or net income (loss). The Company's non-GAAP financial measure, adjusted gross margin, is not standardized; therefore, it may not be possible to compare this financial measure with other companies’ gross margin measures having the same or similar names.

In addition to operating revenues and operating expenses, management also uses the non-GAAP financial measure of adjusted gross margin when evaluating the results of operations for the electric and natural gas distribution segments. Adjusted gross margin for the electric and natural gas distribution segments is calculated by adding back adjustments to operating income (loss). These add-back adjustments include: operation and maintenance expense; depreciation, depletion and amortization expense; and certain taxes, other than income.

Adjusted gross margin includes operating revenues less the cost of electric fuel and purchased power, purchased natural gas sold and certain taxes, other than income. These taxes, other than income, included as a reduction to adjusted gross margin relate to revenue taxes. These segments pass on to their customers the increases and decreases in the wholesale cost of power purchases, natural gas and other fuel supply costs in accordance with regulatory requirements. As such, the segments' revenues are directly impacted by the fluctuations in such commodities. Revenue taxes, which are passed back to customers, fluctuate with revenues as they are calculated as a percentage of revenues. For these reasons, period over period, the segments' operating income (loss) is generally not impacted. The Company's management believes the adjusted gross margin is a useful supplemental financial measure as these items are included in both operating revenues and operating expenses. The Company's management also believes that adjusted gross margin and the remaining operating expenses that calculate operating income (loss) are useful to investors in assessing the Company's utility performance as management has the ability to influence control over the remaining operating expenses.

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The following information reconciles operating income to adjusted gross margin for the electric segment.

(In millions)

Adjustments:

Operating expenses:

Depreciation, depletion and amortization 63.0 58.7 51.0

The following information reconciles operating income to adjusted gross margin for the natural gas distribution segment.

(In millions)

Adjustments:

Operating expenses:

Depreciation, depletion and amortization 84.6 79.6 72.5

Effects of Inflation

Inflation did not have a significant effect on the Company's operations in 2020, 2019 or 2018.

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

The Company is exposed to the impact of market fluctuations associated with commodity prices and interest rates. The Company has policies and procedures to assist in controlling these market risks and from time to time has utilized derivatives to manage a portion of its risk.

Interest rate risk

The Company uses fixed and variable rate long-term debt to partially finance capital expenditures, including acquisitions, and mandatory debt retirements. These debt agreements expose the Company to market risk related to changes in interest rates. The Company manages this risk by taking advantage of market conditions when timing the placement of long-term financing. The Company from time to time has utilized interest rate swap agreements to manage a portion of the Company's interest rate risk and may take advantage of such agreements in the future to minimize such risk. For additional information on the Company's long-term debt, see Item 8 - Notes 8 and 9. At December 31, 2020 and 2019, the Company had no outstanding interest rate hedges.

The following table shows the amount of long-term debt, which excludes unamortized debt issuance costs and discount, and related weighted average interest rates, both by expected maturity dates, as of December 31, 2020.

(Dollars in millions)

Long-term debt:

Weighted average interest rate 1.1 % 4.5 % 3.7 % 4.2 % 4.0 % 4.5 % 4.4 %

Weighted average interest rate — % — % — % 1.0 % — % — % 1.0 %

Commodity price risk

The Company enters into commodity price derivative contracts to minimize the price volatility associated with natural gas costs at its natural gas distribution segment. At December 31, 2020 and 2019, these contracts were not material. For more information on the Company's derivatives, see Item 8 - Note 2.

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Item 8. Financial Statements and Supplementary Data

Management's Report on Internal Control Over Financial Reporting

The management of MDU Resources Group, Inc. is responsible for establishing and maintaining adequate internal control over financial reporting as defined in Rules 13a-15(f) and 15d-15(f) under the Securities Exchange Act of 1934. The Company's internal control system is designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of the Company's financial statements for external purposes in accordance with generally accepted accounting principles in the United States of America.

All internal control systems, no matter how well designed, have inherent limitations. Therefore, even those systems determined to be effective can provide only reasonable assurance with respect to financial statement preparation and presentation. Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

Management assessed the effectiveness of the Company's internal control over financial reporting as of December 31, 2020. In making this assessment, management used the criteria set forth by the Committee of Sponsoring Organizations of the Treadway Commission (COSO) in Internal Control-Integrated Framework (2013).

Based on our evaluation under the framework in Internal Control-Integrated Framework (2013), management concluded that the Company's internal control over financial reporting was effective as of December 31, 2020.

The effectiveness of the Company's internal control over financial reporting as of December 31, 2020, has been audited by Deloitte & Touche LLP, an independent registered public accounting firm, as stated in their report.

/s/ David L. Goodin /s/ Jason L. Vollmer

David L. Goodin Jason L. Vollmer

President and Chief Executive Officer Vice President and Chief Financial Officer

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Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of MDU Resources Group, Inc.

Opinion on the Financial Statements

We have audited the accompanying consolidated balance sheets of MDU Resources Group, Inc. and subsidiaries (the "Company") as of December 31, 2020 and 2019, the related consolidated statements of income, comprehensive income, equity, and cash flows for each of the three years in the period ended December 31, 2020, and the related notes and the financial statement schedules listed in the Index at Item 15 (collectively referred to as the "financial statements"). In our opinion, the financial statements present fairly, in all material respects, the financial position of the Company as of December 31, 2020 and 2019, and the results of its operations and its cash flows for each of the three years in the period ended December 31, 2020, in conformity with accounting principles generally accepted in the United States of America.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the Company's internal control over financial reporting as of December 31, 2020, based on criteria established in Internal Control-Integrated Framework (2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission and our report dated February 19, 2021, expressed an unqualified opinion on the Company's internal control over financial reporting.

Basis for Opinion

These financial statements are the responsibility of the Company's management. Our responsibility is to express an opinion on the Company's financial statements based on our audits. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audits in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether the financial statements are free of material misstatement, whether due to error or fraud. Our audits included performing procedures to assess the risks of material misstatement of the financial statements, whether due to error or fraud, and performing procedures that respond to those risks. Such procedures included examining, on a test basis, evidence regarding the amounts and disclosures in the financial statements. Our audits also included evaluating the accounting principles used and significant estimates made by management, as well as evaluating the overall presentation of the financial statements. We believe that our audits provide a reasonable basis for our opinion.

Critical Audit Matters

The critical audit matters communicated below are matters arising from the current-period audit of the financial statements that were communicated or required to be communicated to the audit committee and that (1) relate to accounts or disclosures that are material to the financial statements and (2) involved our especially challenging, subjective, or complex judgments. The communication of critical audit matters does not alter in any way our opinion on the financial statements, taken as a whole, and we are not, by communicating the critical audit matters below, providing separate opinions on the critical audit matters or on the accounts or disclosures to which they relate.

Revenue from Contracts with Customers-Construction Contract Revenue-Refer to Notes 2 and 3 to the financial statements

Critical Audit Matter Description

The Company recognizes construction contract revenue over time using an input method based on the cost-to-cost measure of progress as it best depicts the transfer of assets to the customer. Under this method of measuring progress, costs incurred are compared with total estimated costs of the performance obligation and revenues are recorded proportionately to the costs incurred. Ordinarily the Company’s contracts represent a single distinct performance obligation due to the highly interdependent and interrelated nature of the underlying goods or services. For the year ended December 31, 2020, the Company recognized $3.1 billion of construction contract revenue.

Given the judgments necessary to estimate total costs and profit for the performance obligations used to recognize revenue for construction contracts, auditing such estimates required extensive audit effort due to the volume and complexity of construction contracts and a high degree of auditor judgment when performing audit procedures and evaluating the results of those procedures.

How the Critical Audit Matter Was Addressed in the Audit

Our audit procedures related to management’s estimates of total costs and profit for the performance obligations used to recognize revenue for certain construction contracts included the following, among others:

•We tested the design and operating effectiveness of management's controls over construction contract revenue, including those over management’s estimation of total costs and profit for the performance obligations.

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•We developed an expectation of the amount of construction contract revenues for certain performance obligations based on prior year markups, and taking into account current year events, applied to the construction contract costs in the current year and compared our expectation to the amount of construction contract revenues recorded by management.

•We selected a sample of construction contracts and performed the following:

•Evaluated whether the contracts were properly included in management’s calculation of construction contract revenue based on the terms and conditions of each contract, including whether continuous transfer of control to the customer occurred as progress was made toward fulfilling the performance obligation.

•Compared the transaction prices to the consideration expected to be received based on current rights and obligations under the contracts and any modifications that were agreed upon with the customers.

•Evaluated management’s identification of distinct performance obligations by evaluating whether the underlying goods, services, or both were highly interdependent and interrelated.

•Tested the accuracy and completeness of the costs incurred to date for the performance obligation.

•Evaluated the estimates of total cost and profit for the performance obligation by:

◦Comparing total costs incurred to date to the costs management estimated to be incurred to date and selecting specific cost types to compare costs incurred to date to management's estimated costs at completion.

◦Evaluating management’s ability to achieve the estimates of total cost and profit by performing corroborating inquiries with the Company’s project managers and engineers, and comparing the estimates to management’s work plans, engineering specifications, and supplier contracts.

◦Comparing management’s estimates for the selected contracts to costs and profits of similar performance obligations, when applicable.

•Tested the mathematical accuracy of management’s calculation of construction contract revenue for the performance obligation.

•We evaluated management’s ability to estimate total costs and profits accurately by comparing actual costs and profits to management’s historical estimates for performance obligations that have been fulfilled.

Regulatory Matters-Impact of Rate Regulation on the Financial Statements-Refer to Notes 2 and 20 to the financial statements

Critical Audit Matter Description

Through the Company’s regulated utility businesses, it provides electric and natural gas services to customers, and generates, transmits, and distributes electricity. The Company is subject to rate regulation by federal and state utility regulatory agencies (collectively, the “Commissions”), which have jurisdiction with respect to the rates of electric and natural gas distribution companies in states where the Company operates. The Company’s regulated utility businesses account for certain income and expense items under the provisions of regulatory accounting, which requires these businesses to defer as regulatory assets or liabilities certain items that would have otherwise been reflected as expense or income, respectively, based on the expected regulatory treatment in future rates. The expected recovery or flowback of these deferred items generally is based on specific ratemaking decisions or precedent for each item.

Rates are determined and approved in regulatory proceedings based on an analysis of the Company’s costs to provide utility service and a return on the Company’s investment in the regulated utility businesses. Regulatory decisions can have an impact on the recovery of costs, the rate of return earned on investment, and the timing and amount of assets to be recovered by rates. The regulation of rates is premised on the full recovery of prudently incurred costs and a reasonable rate of return on invested capital. Decisions to be made by the Commissions in the future will impact the accounting for regulated operations.

Accounting for the economics of rate regulation impacts multiple financial statement line items and disclosures, such as property, plant, and equipment; regulatory assets and liabilities; operating revenues; operation and maintenance expense; and depreciation expense. We identified the impact of rate regulation as a critical audit matter due to the significant judgments made by management to support its assertions about impacted account balances and disclosures and the degree of subjectivity involved in assessing the impact of future regulatory orders on the financial statements. Management judgments include assessing the likelihood of (1) recovery in future rates of incurred costs and (2) refunds to customers. Given management’s accounting judgments are based on assumptions about the outcome of future decisions by the Commissions, auditing these judgments requires specialized knowledge of accounting for rate regulation due to its inherent complexities.

How the Critical Audit Matter Was Addressed in the Audit

Our audit procedures related to the uncertainty of future decisions by the Commissions included the following, among others:

•We tested the design and operating effectiveness of management’s controls over the evaluation of the likelihood of (1) the recovery in future rates of costs incurred as property, plant, and equipment and deferred as regulatory assets; and (2) a refund or a future reduction in rates that should be reported as regulatory liabilities. We tested management’s controls over the initial recognition of amounts as regulatory assets or liabilities; and the monitoring and evaluation of regulatory developments that may affect the likelihood of recovering costs in future rates or of a future reduction in rates.

•We evaluated the Company’s disclosures related to the impacts of rate regulation, including the balances recorded and regulatory developments.

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•We read relevant regulatory orders issued by the Commissions for the Company and other public utilities in the Company’s significant jurisdictions, regulatory statutes, interpretations, procedural memorandums, filings made by interveners, and other publicly available information to assess the likelihood of recovery in future rates or of a future reduction in rates based on precedents of the treatment of similar costs under similar circumstances. We evaluated the external information and compared to management’s recorded regulatory asset and liability balances for completeness.

•For regulatory matters in process, we inspected the Company’s filings with the Commissions and the filings with the Commissions by intervenors that may impact the Company’s future rates, for any evidence that might contradict management’s assertions.

•We obtained an analysis from management regarding probability of recovery for regulatory assets or refund or future reduction in rates for regulatory liabilities not yet addressed in a regulatory order to assess management’s assertion that amounts are probable of recovery, or a future reduction in rates.

/s/ Deloitte & Touche LLP

Minneapolis, Minnesota

We have served as the Company's auditor since 2002.

58 MDU Resources Group, Inc. Form 10-K

Part II

Report of Independent Registered Public Accounting Firm

To the Stockholders and the Board of Directors of MDU Resources Group, Inc.

Opinion on Internal Control over Financial Reporting

We have audited the internal control over financial reporting of MDU Resources Group, Inc. and subsidiaries (the "Company") as of December 31, 2020, based on criteria established in Internal Control-Integrated Framework(2013) issued by the Committee of Sponsoring Organizations of the Treadway Commission (COSO). In our opinion, the Company maintained, in all material respects, effective internal control over financial reporting as of December 31, 2020, based on criteria established in Internal Control-Integrated Framework (2013) issued by COSO.

We have also audited, in accordance with the standards of the Public Company Accounting Oversight Board (United States) (PCAOB), the consolidated financial statements and financial statement schedules as of and for the year ended December 31, 2020, of the Company and our report dated February 19, 2021, expressed an unqualified opinion on those consolidated financial statements and financial statement schedules.

Basis for Opinion

The Company's management is responsible for maintaining effective internal control over financial reporting and for its assessment of the effectiveness of internal control over financial reporting, included in the accompanying Management's Report on Internal Control Over Financial Reporting. Our responsibility is to express an opinion on the Company's internal control over financial reporting based on our audit. We are a public accounting firm registered with the PCAOB and are required to be independent with respect to the Company in accordance with the U.S. federal securities laws and the applicable rules and regulations of the Securities and Exchange Commission and the PCAOB.

We conducted our audit in accordance with the standards of the PCAOB. Those standards require that we plan and perform the audit to obtain reasonable assurance about whether effective internal control over financial reporting was maintained in all material respects. Our audit included obtaining an understanding of internal control over financial reporting, assessing the risk that a material weakness exists, testing and evaluating the design and operating effectiveness of internal control based on the assessed risk, and performing such other procedures as we considered necessary in the circumstances. We believe that our audit provides a reasonable basis for our opinion.

Definition and Limitations of Internal Control over Financial Reporting

A company’s internal control over financial reporting is a process designed to provide reasonable assurance regarding the reliability of financial reporting and the preparation of financial statements for external purposes in accordance with generally accepted accounting principles. A company’s internal control over financial reporting includes those policies and procedures that (1) pertain to the maintenance of records that, in reasonable detail, accurately and fairly reflect the transactions and dispositions of the assets of the company; (2) provide reasonable assurance that transactions are recorded as necessary to permit preparation of financial statements in accordance with generally accepted accounting principles, and that receipts and expenditures of the company are being made only in accordance with authorizations of management and directors of the company; and (3) provide reasonable assurance regarding prevention or timely detection of unauthorized acquisition, use, or disposition of the company’s assets that could have a material effect on the financial statements.

Because of its inherent limitations, internal control over financial reporting may not prevent or detect misstatements. Also, projections of any evaluation of effectiveness to future periods are subject to the risk that controls may become inadequate because of changes in conditions, or that the degree of compliance with the policies or procedures may deteriorate.

/s/ Deloitte & Touche LLP

Minneapolis, Minnesota

MDU Resources Group, Inc. Form 10-K 59

Part II

Consolidated Statements of Income

(In thousands, except per share amounts)

Operating revenues:

Operating expenses:

Operation and maintenance:

Income (loss) from discontinued operations, net of tax (322) 287 2,932

Earnings per share - basic:

Income from continuing operations $ 1.95 $ 1.69 $ 1.38

Discontinued operations, net of tax — — .01

Earnings per share - basic $ 1.95 $ 1.69 $ 1.39

Earnings per share - diluted:

Income from continuing operations $ 1.95 $ 1.69 $ 1.38

Discontinued operations, net of tax — — .01

Earnings per share - diluted $ 1.95 $ 1.69 $ 1.39

The accompanying notes are an integral part of these consolidated financial statements.

60 MDU Resources Group, Inc. Form 10-K

Part II

Consolidated Statements of Comprehensive Income

(In thousands)

Other comprehensive income (loss):

Postretirement liability adjustment:

Foreign currency translation adjustment:

Foreign currency translation adjustment — — 188

Net unrealized gain (loss) on available-for-sale investments:

Net unrealized gain (loss) on available-for-sale investments 51 174 (13)

The accompanying notes are an integral part of these consolidated financial statements.

MDU Resources Group, Inc. Form 10-K 61

Part II

Consolidated Balance Sheets

Assets (In thousands, except shares and per share amounts)

Current assets:

Noncurrent assets:

Less accumulated depreciation, depletion and amortization 3,133,831 2,991,486

Liabilities and Stockholders' Equity

Current liabilities:

Short-term borrowings $ 50,000 $ —

Long-term debt due within one year 1,555 16,540

Regulatory liabilities due within one year 31,450 42,935

Operating lease liabilities due within one year 33,655 31,664

Noncurrent liabilities:

Commitments and contingencies

Stockholders' equity:

Accumulated other comprehensive loss (48,078) (42,102)

The accompanying notes are an integral part of these consolidated financial statements.

62 MDU Resources Group, Inc. Form 10-K

Part II

Consolidated Statements of Equity

OtherPaid-in Capital Retained Earnings Accumu-latedOther Compre-hensive Loss

Common Stock Treasury Stock

Shares Amount Shares Amount Total

Cumulative effect of adoption of ASC 606 — — — (970) — — — (970)

Other comprehensive income — — — — 6,951 — — 6,951

Dividends declared on common stock — — — (156,453) — — — (156,453)

Stock-based compensation — — 5,060 — — — — 5,060

Other comprehensive loss — — — — (3,760) — — (3,760)

Dividends declared on common stock — — — (162,408) — — — (162,408)

Stock-based compensation — — 7,353 — — — — 7,353

Other comprehensive loss — — — — (5,976) — — (5,976)

Dividends declared on common stock — — — (168,489) — — — (168,489)

The accompanying notes are an integral part of these consolidated financial statements.

MDU Resources Group, Inc. Form 10-K 63

Part II

Consolidated Statements of Cash Flows

(In thousands)

Operating activities:

Income (loss) from discontinued operations, net of tax (322) 287 2,932

Changes in current assets and liabilities, net of acquisitions:

Net cash provided by (used in) discontinued operations (1,375) 464 (3,942)

Investing activities:

Net proceeds from sale or disposition of property and other 35,557 29,812 26,100

Net cash provided by discontinued operations — — 1,236

Financing activities:

Proceeds from issuance of common stock 3,385 106,848 —

Payments of stock issuance costs — — (10)

Repurchase of common stock — — (5,020)

Tax withholding on stock-based compensation (362) (3,015) (2,330)

Effect of exchange rate changes on cash and cash equivalents — — (1)

The accompanying notes are an integral part of these consolidated financial statements.

64 MDU Resources Group, Inc. Form 10-K

Part II

Notes to Consolidated Financial Statements

Note 1 - Basis of Presentation

The abbreviations and acronyms used throughout are defined following the Notes to Consolidated Financial Statements. The consolidated financial statements of the Company include the accounts of the following businesses: electric, natural gas distribution, pipeline, construction materials and contracting, construction services and other. The electric and natural gas distribution businesses, as well as a portion of the pipeline business, are regulated. Construction materials and contracting, construction services and the other businesses, as well as a portion of the pipeline business, are non-regulated. For further descriptions of the Company's businesses, see Note 17.

On January 2, 2019, the Company announced the completion of the Holding Company Reorganization, which resulted in Montana-Dakota becoming a subsidiary of the Company. The purpose of the reorganization was to make the public utility division into a subsidiary of the holding company, just as the other operating companies are wholly owned subsidiaries.

In March 2020, the World Health Organization declared the outbreak of COVID-19 a pandemic, and the President of the United States declared the COVID-19 outbreak as a national emergency. Governmental restrictions and guidelines implemented to control the spread of COVID-19 reduced commercial and interpersonal activity throughout the Company's areas of operation. Most of the Company's products and services are considered essential and accordingly operations have been generally allowed to continue. The Company has experienced some inefficiency impacts, including operation suspensions and interruptions at some locations to carry out preventive measures or in response to instances of positive tests or quarantines. The Company has assessed the impacts of the COVID-19 pandemic on its results of operations for the twelve months ended December 31, 2020, and determined there were no material adverse impacts.

In the first quarter of 2020, the Company recorded an out-of-period adjustment to correct the recognition of revenue on a construction contract, which was the result of an overstatement of operating revenue and receivables of $7.7 million and an understatement of operating expense and accounts payable of $1.2 million in the year ended December 31, 2019. This adjustment resulted in an after-tax reduction to net income of $6.7 million in the first quarter of 2020. The Company evaluated the impact of the out-of-period adjustment and concluded it was not material to any previously issued interim and annual consolidated financial statements and the adjustment was not material to the three months ended March 31, 2020, or the twelve months ended December 31, 2020.

In the fourth quarter of 2020, the Company recorded an out-of-period adjustment to correct the recognition of net periodic benefit cost and other comprehensive income associated with the Company's benefit plans, which was the result of the previous overstatement of benefit plan expenses of $6.5 million, understatement of accumulated other comprehensive loss of $2.7 million and overstatement of regulatory liabilities of $3.8 million from 2006 through 2020. This adjustment resulted in an after-tax increase to net income of $4.4 million in the fourth quarter of 2020. The Company evaluated the impact of the out-of-period adjustment, individually and in the aggregate with the previously mentioned out-of-period adjustment, and concluded it was not material to any previously issued interim and annual consolidated financial statements and the adjustment was not material to the three and twelve months ended December 31, 2020.

Effective January 1, 2020, the Company adopted the requirements of the ASU on the measurement of credit losses on certain financial instruments following a modified retrospective approach, as further discussed in Note 2. As such, results for reporting periods beginning on January 1, 2020, are presented under the new guidance, while prior period amounts are not adjusted and continue to be reported in accordance with historic accounting. The Company's adoption of this guidance did not have a material impact on its financial reporting.

The assets and liabilities of the Company's discontinued operations have been classified as held for sale and are included in prepayments and other current assets, noncurrent assets - other and other accrued liabilities on the Consolidated Balance Sheets and are not material to the financial statements for any period presented. The results and supporting activities are shown in income (loss) from discontinued operations on the Consolidated Statements of Income. Unless otherwise indicated, the amounts presented in the accompanying notes to the consolidated financial statements relate to the Company's continuing operations.

Management has also evaluated the impact of events occurring after December 31, 2020, up to the date of issuance of these consolidated financial statements.

Principles of consolidation

The consolidated financial statements were prepared in accordance with GAAP and include the accounts of the Company and its wholly-owned subsidiaries. All intercompany balances and transactions have been eliminated in consolidation, except for certain transactions related to the Company's regulated operations in accordance with GAAP. For more information on intercompany revenues, see Note 17.

The statements also include the Company's ownership interests in the assets, liabilities and expenses of jointly owned electric transmission and generating facilities. See Note 19 for additional information.

MDU Resources Group, Inc. Form 10-K 65

Part II

Use of estimates

The preparation of financial statements in conformity with GAAP requires the Company to make estimates and assumptions that affect the reported amounts of assets and liabilities, and disclosure of contingent assets and liabilities, at the date of the financial statements, as well as the reported amounts of revenues and expenses during the reporting period. Estimates are used for items such as long-lived assets and goodwill; fair values of acquired assets and liabilities under the acquisition method of accounting; aggregate reserves; property depreciable lives; tax provisions; revenue recognized using the cost-to-cost measure of progress for contracts; expected credit losses; environmental and other loss contingencies; regulatory assets expected to be recovered in rates charged to customers; costs on construction contracts; unbilled revenues; actuarially determined benefit costs; asset retirement obligations; lease classification; present value of right-of-use assets and lease liabilities; and the valuation of stock-based compensation. As additional information becomes available, or actual amounts are determinable, the recorded estimates are revised. Consequently, operating results can be affected by revisions to prior accounting estimates.

Note 2 - Significant Accounting Policies

New accounting standards

Recently adopted accounting standards

ASU 2016-13 - Measurement of Credit Losses on Financial Instruments In June 2016, the FASB issued guidance on the measurement of credit losses on certain financial instruments. The guidance introduced a new impairment model known as the current expected credit loss model that replaced the incurred loss impairment methodology previously included under GAAP. This guidance required entities to present certain investments in debt securities, trade accounts receivable and other financial assets at their net carrying value of the amount expected to be collected on the financial statements. The Company adopted the guidance on January 1, 2020, using a modified retrospective approach.

The Company formed an implementation team to review and assess existing financial assets to identify and evaluate the financial assets subject to the new current expected credit loss model. The Company assessed the impact of the guidance on its processes and internal controls and has identified and updated existing internal controls and processes to ensure compliance with the new guidance; such modifications were deemed insignificant. During the assessment phase, the Company identified the complete portfolio of assets subject to the current expected credit loss model. The Company determined the guidance did not have a material impact on its results of operations, financial position, cash flows or disclosures and did not record a material cumulative effect adjustment upon adoption. See Receivables and allowance for expected credit losses within this note for additional information on the Company's expected credit losses.

ASU 2018-13 - Changes to the Disclosure Requirements for Fair Value Measurement In August 2018, the FASB issued guidance on modifying the disclosure requirements on fair value measurements as part of the disclosure framework project. The guidance modified, among other things, the disclosures required for Level 3 fair value measurements, including the range and weighted average of significant unobservable inputs. The guidance removed, among other things, the disclosure requirement to disclose transfers between Levels 1 and 2. The Company adopted the guidance on January 1, 2020, and determined it did not have a material impact on its disclosures.

Recently issued accounting standards not yet adopted

ASU 2018-14 - Changes to the Disclosure Requirements for Defined Benefit Plans In August 2018, the FASB issued guidance on modifying the disclosure requirements for employers that sponsor defined benefit pension or other postretirement plans as part of the disclosure framework project. The guidance removed disclosures that are no longer considered cost beneficial, clarifies the specific requirements of disclosures and added disclosure requirements identified as relevant. The guidance added, among other things, the requirement to include an explanation for significant gains and losses related to changes in benefit obligations for the period. The guidance removed, among other things, the disclosure requirement to disclose the amount of net periodic benefit costs to be amortized over the next fiscal year from accumulated other comprehensive income (loss) and the effects a one percentage point change in assumed health care cost trend rates will have on certain benefit components. The guidance was effective for the Company on January 1, 2021, and must be applied on a retrospective basis. The Company determined the new guidance will not materially impact its consolidated financial statement disclosures.

ASU 2019-12 - Simplifying the Accounting for Income Taxes In December 2019, the FASB issued guidance on simplifying the accounting for income taxes by removing certain exceptions in ASC 740 and providing simplification amendments. The guidance removed exceptions on intraperiod tax allocations and reporting and provided simplification on accounting for franchise taxes, tax basis goodwill and tax law changes. The Company adopted the guidance on January 1, 2021, and determined it did not have a material impact on its results of operations, financial position, cash flows and disclosures.

ASU 2020-04 - Reference Rate Reform In March 2020, the FASB issued optional guidance to ease the facilitation of the effects of reference rate reform on financial reporting. The guidance applies to certain contract modifications, hedging relationships and other transactions that reference LIBOR or another reference rate expected to be discontinued because of reference rate reform. LIBOR is expected to be retired with a full phase-out by the end of 2021 and replaced by new reference rates, which includes SOFR. The guidance can be applied beginning in the interim period that includes March 12, 2020, and cannot be applied to contract modifications or hedging relationships entered into or evaluated after December 31, 2022. The Company has updated its credit agreements to include language regarding the successor or alternate rate to LIBOR, and a review of other contracts and agreements is on-going. The Company does not expect the guidance to have a material impact on its results of operations, financial position, cash flows or disclosures.

66 MDU Resources Group, Inc. Form 10-K

Part II

Cash and cash equivalents

The Company considers all highly liquid investments purchased with an original maturity of three months or less to be cash equivalents.

Revenue recognition

Revenue is recognized when a performance obligation is satisfied by transferring control over a product or service to a customer. Revenue is measured based on consideration specified in a contract with a customer and excludes any sales incentives and amounts collected on behalf of third parties. The Company is considered an agent for certain taxes collected from customers. As such, the Company presents revenues net of these taxes at the time of sale to be remitted to governmental authorities, including sales and use taxes.

The electric and natural gas distribution segments generate revenue from the sales of electric and natural gas products and services, which includes retail and transportation services. These segments establish a customer's retail or transportation service account based on the customer's application/contract for service, which indicates approval of a contract for service. The contract identifies an obligation to provide service in exchange for delivering or standing ready to deliver the identified commodity; and the customer is obligated to pay for the service as provided in the applicable tariff. The product sales are based on a fixed rate that includes a base and per-unit rate, which are included in approved tariffs as determined by state or federal regulatory agencies. The quantity of the commodity consumed or transported determines the total per-unit revenue. The service provided, along with the product consumed or transported, are a single performance obligation because both are required in combination to successfully transfer the contracted product or service to the customer. Revenues are recognized over time as customers receive and consume the products and services. The method of measuring progress toward the completion of the single performance obligation is on a per-unit output method basis, with revenue recognized based on the direct measurement of the value to the customer of the goods or services transferred to date. For contracts governed by the Company’s utility tariffs, amounts are billed monthly with the amount due between 15 and 22 days of receipt of the invoice depending on the applicable state’s tariff. For other contracts not governed by tariff, payment terms are net 30 days. At this time, the segment has no material obligations for returns, refunds or other similar obligations.

MDU US Equity

MDU · 10-K · period ended 2020-12-31

Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Item 8. Financial Statements and Supplementary Data

MDU US Equity☆

MDU · 10-K · period ended 2020-12-31

Item 7. Management's Discussion and Analysis of Financial Condition and Results of Operations

Item 7A. Quantitative and Qualitative Disclosures About Market Risk

Item 8. Financial Statements and Supplementary Data

MDU US Equity