What does a real rate tell you?
A larger cash balance and greater purchasing power are different outcomes. A nominal interest rate describes the cash return, while a real rate considers the change in prices. Real return is broader: fund, equity or gold performance can also be adjusted for inflation. For an investment, account for ending value and cash distributions rather than looking only at an interest payment.
Exact calculation and approximation
For matching periods, exact real return is (1 + net nominal return) / (1 + inflation) minus 1. Convert percentages to decimals first. A 30% return and 25% inflation give 1.30 / 1.25 minus 1, or 4%. Subtracting the two percentages gives a five-point approximation that overstates this result. The formula compares outcomes; it does not forecast future prices or returns.
| Assumption | Nominal ending balance | Value in starting purchasing power | Real return |
|---|---|---|---|
| 30% net return, 25% inflation | TRY130,000 | TRY104,000 | 4.00% |
| 30% net return, 40% inflation | TRY130,000 | TRY92,857.14 | −7.14% |
| 20% net return, 25% inflation | TRY120,000 | TRY96,000 | −4.00% |
What happens to TRY100,000?
These rates are scenarios, not current market data or bank offers. TRY100,000 earning a net 30% becomes TRY130,000. With prices up 25%, the initial basket now costs TRY125,000, and the balance is worth TRY104,000 at starting prices. With inflation of 40%, that same balance is worth TRY92,857.14 at starting prices. A positive nominal gain can coexist with a loss of purchasing power.
Align term, deductions and currency
Comparing a monthly return with annual inflation is invalid. Use the price-index change over the actual holding period. Deduct applicable taxes and separate charges before calculating a net return; the table already assumes net rates, so no second deduction is applied. For the lira purchasing power of a foreign-currency investment, include the currency conversion at both endpoints. Contributions during the period require a cash-flow-aware calculation.
Expected real rates versus realized outcomes
A forward-looking calculation using expected inflation produces an expected real rate, not a guaranteed outcome. Realized inflation may differ. A consumer-price index also represents an average basket, which may not match spending concentrated in rent, education or imports. Real return does not measure credit risk, liquidity or principal protection. Keep those characteristics separate when comparing products.
Related market pages and tools
Sources and further reading
Numerical examples are illustrative scenarios, not company data, bank offers or current tax rates.
This content is general information and financial education. It is not personalized investment advice or a recommendation to buy or sell.