Methodology

Inflation adjustment

Adjusted value = original value × (CPI level today ÷ CPI level at the original date), using the monthly CPI-U series (BLS, retrieved via FRED, code CPIAUCSL). This is the same ratio method used by the official BLS calculator.

Investment simulations

The "had I invested" and comparison pages use monthly closing prices. Stocks and funds use adjusted closes (dividends and splits reinvested); the S&P 500 here is the price index, without dividends, so its total return would be higher, and we flag that on every page. Gold and silver pay no interest, so their return is price alone. A currency is shown as an exchange rate against the dollar — cash held in it earns no interest, so a rate move is not a return. Home prices are the typical value per square meter from Redfin, the value of the property itself, excluding rent, leverage, taxes and maintenance.

Stated limitations

• CPI measures average urban consumption; your personal inflation differs.
• Purchasing-power adjustment is not an investment return.
• Pre-1913 values cannot be adjusted — the official series starts there.
• Past performance is shown for what it was, not a forecast — the entry date drove most outcomes.

Descriptive, educational content computed from official public data. Not investment advice. Past performance does not guarantee future results.