Real Returns — the Inflation Tax

The subtraction

Real return ≈ nominal return − inflation. Your 5% bond yield with 4% inflation is a 1% real return before tax — and taxes are charged on the NOMINAL gain, so high inflation can leave you with a negative after-tax real return on "positive-yield" bonds. Compounding silently: 4% inflation halves purchasing power in ~18 years.

Who wins and loses

Inflation hurts: cash holders, long-duration bonds (fixed coupons buy less), and companies that cannot pass through costs. Inflation helps: owners of real assets (property, commodities), debtors (they repay in cheaper dollars), and businesses with pricing power — the margin lesson (day 17) is an inflation lesson: pass-through ability IS the moat under inflation.

The market connection

Rising inflation → rising rates (Fed response) → the day-39 channels fire. Falling inflation is the double gift: real returns rise AND the discount-rate pressure lifts. This is why CPI prints move everything — they are the Fed's input and the real-return denominator at once.

Sources

• Real Rate of ReturnInvestopedia
• How the Economic Machine WorksRay Dalio