What $100 a month would have grown to
Start with $100 in January 2000 and add $100 at every later monthly observation in the gold file, and you would have put in $32,200 and held a notional position worth $167,054 by Oct 2026 — 5.19× the money contributed, a 10.7% money-weighted return (XIRR). The same schedule on the other official series is in the table below.
Data: World Bank Commodity Price Data (CC BY 4.0), FHFA HPI®, U.S. Treasury yields, BLS CPI-U. Historical illustration, not financial advice; ignores fees, storage and taxes. Details
How the $100-a-month math works
The first $100 buys units at the first monthly price on or after the start date. Each later month in the file, another $100 buys additional units at that month’s official price (or index level). We do not skip months that exist in the file, and we do not add a contribution in a missing month. Because money goes in over time, we report a money-weighted return (XIRR) rather than a lump-sum CAGR for the contribution plan. A lump-sum column shows what would have happened if the same total dollars had all gone in on the first day — usually a different, often more favorable, path when prices generally rose.
Computed results
| Series | Start | Total contributed | End value | Multiple | XIRR | Same total as a lump sum |
|---|---|---|---|---|---|---|
| Gold | Jan 2000 | $32,200 | $167,054 | 5.19× | 10.7% | $465,426 (10.5% CAGR) |
| U.S. house prices (FHFA HPI) | Jan 2000 | $32,000 | $64,507 | 2.02× | 4.9% | $105,430 (4.6% CAGR) |
| U.S. 3-month Treasury bills (rolled) | Jan 2000 | $32,300 | $42,512 | 1.32× | — | $55,222 (2.0% CAGR) |
| Gold | Jan 2015 | $14,200 | $34,841 | 2.45× | 14.5% | $46,596 (10.6% CAGR) |
| U.S. house prices (FHFA HPI) | Jan 2015 | $14,000 | $20,681 | 1.48× | 6.6% | $30,367 (6.9% CAGR) |
| U.S. 3-month Treasury bills (rolled) | Jan 2015 | $14,300 | $17,147 | 1.20× | 3.0% | $18,492 (2.2% CAGR) |
Housing figures remain an unlevered national index path, not a mortgage. T-bills use our computed yield-roll index. Gold is a spot average, not an ETF. Inflation-adjusted values for any row are available with the checkbox on the calculator or on the real vs nominal page.