Glossary
Terms used on this calculator, in one place. Formal source notes live on the methodology page.
CAGR
Compound annual growth rate. For a lump sum, (end value ÷ starting amount) raised to (1 ÷ years), minus 1. Years here are actual days ÷ 365.25. It is not used when monthly contributions make the cash flows irregular.
XIRR / money-weighted return
An annualized rate that sets the net present value of all cash flows to zero (contributions negative, ending value positive). We use it when money is added over time, because a simple CAGR would ignore when the dollars went in.
Nominal vs real
Nominal figures are in the dollars of each date. Real figures on this site are expressed in start-month dollars by scaling with BLS CPI-U. See Real vs nominal returns.
CPI-U
The Consumer Price Index for All Urban Consumers, all items, U.S. city average, not seasonally adjusted (BLS series CUUR0000SA0). A public-domain U.S. government index. We use the last published month on or before each date.
Spot price
A monthly average cash-market price from the World Bank Pink Sheet, not the price of an ETF, futures contract, or brokerage product. No dividends, storage, or roll yield are included.
FHFA HPI®
The FHFA House Price Index, Purchase-Only, United States, monthly, not seasonally adjusted. A constant-quality repeat-sales index (January 1991 = 100). It is not a median sale price and not the value of a particular house.
Rolled 3-month Treasury bills
A wealth index we compute from official Daily Treasury Par Yield Curve Rates for the 3-month tenor. The index starts at 100 and each later month grows by the prior month’s average daily yield divided by 12. It is an approximation, not a published Treasury total-return index.
Par yield
The coupon rate a Treasury security would need, at par, to match the official yield curve on that day. We average the daily 3-month par yields in each month.
Units
The notional quantity bought: initial amount ÷ start-month price, plus any later contributions ÷ that month’s price.
Hold-to-today ranking
For each January start, a lump sum is held until the latest month in the file, then ranked (usually by CAGR). Early starts have longer windows than late starts.
Past performance
Historical results on these official series are not indicative of future results. You can lose money. Nothing here is financial advice.