The real interest rate is the nominal interest rate adjusted for inflation — what lenders actually earn and borrowers actually pay after purchasing power erosion.

This chart uses the Fisher equation applied to market-determined rates: Real Rate = 3-Month T-Bill Secondary Market Rate minus CPI Year-over-Year Inflation. The T-bill rate is set by the market, not by the Federal Reserve. When the real rate is negative, inflation is outpacing the short-term market return — historically associated with financial repression and negative real returns for savers.

Data Source: U.S. Federal Reserve Economic Data (FRED)

• T-Bill Rate: TB3MS (monthly, from 1934)
• CPI: CPIAUCNS (not seasonally adjusted, monthly, from 1913)