Transparency is a feature. This page explains what calendar-period returns measure and why we compute them — in plain terms. The precise formulas and numeric conventions are documented in our internal methodology; the summary here is deliberate, not an omission.
This tool takes a series of simple period returns — each one stamped with the calendar date it was earned on, expressed as a decimal fraction — and rolls them up into the four standard reporting windows: month-to-date (MTD), quarter-to-date (QTD), year-to-date (YTD), and since inception. Every window is measured relative to an anchor date (the "as of" date), which defaults to the most recent date in the series but can be set to any point you choose.
Each window looks at the returns whose dates fall inside it — this month, this calendar quarter, this calendar year, or the entire history — and compounds them geometrically, so gains are treated as reinvested rather than simply added up. Membership is decided by the calendar date on each return, not by its position in the list, so the order the data arrives in never changes the answer. Nothing dated after the anchor is ever counted, which lets you reconstruct what any window looked like as of an earlier point in time. Quarters are the usual calendar quarters (January–March, April–June, July–September, October–December). A positive figure means the window gained over the period; it can be negative.
