Real rate of return

An investment can grow in dollars while losing ground to rising prices. A positive nominal return can still be a negative real return if inflation is higher. Real return compares investment growth with the change in prices over the same period. A 10% nominal return with 4% inflation produces a real return of about 5.77%, not exactly 6%.

In a sentence

• "My investment earns 10% while inflation is 4%, so my real rate of return is about 5.77%."
• "The nominal return tells me how my investment grows in dollars; the real rate of return tells me how its purchasing power changes."
• "Adding money increases my account balance, but the deposit is not part of my real rate of return."

How it's calculated

The real rate of return compares two growth factors, investment growth and price growth.

Real rate of return = (1 + nominal return) ÷ (1 + inflation rate) − 1

1. Choose one measurement period. Use the investment return and inflation over matching dates, rather than comparing a lifetime investment gain with one year's inflation.
2. Find the nominal investment return. Include investment income as well as price changes, using a return calculation that accounts for deposits and withdrawals rather than treating them as gains or losses.
3. Enter both rates as decimals. A 10% return becomes 0.10, and 4% inflation becomes 0.04.
4. Divide the investment growth factor by the price growth factor, subtract one, and convert the result to a percentage.

For the example, the calculation is (1.10 ÷ 1.04) − 1, or about 5.77%. Dividing by the price growth factor translates the ending investment value into the purchasing power of dollars at the start.

An example

You invest $10,000 for one year and earn a 10% nominal total return while inflation is 4%. There are no further deposits or withdrawals, all investment income stays invested, and the example ignores fees and taxes.

The nominal gain is $1,000, but after restating the whole ending balance in starting-year dollars, the purchasing-power gain is $576.92. You need $10,400 at year end just to match the starting investment's purchasing power.

Why it matters

Real return connects investment performance to purchasing power, which is what a long-term savings goal ultimately needs. A larger retirement balance is not necessarily able to buy more if living costs have risen faster. The inflation adjustment separates a gain in dollars from a gain in what those dollars can purchase.

Real return also keeps planning assumptions consistent. Use nominal returns with future-dollar targets, or real returns with targets expressed in today's dollars. Neither an assumed nominal return nor an assumed real return is a promise of future performance.

Real rate of return versus nominal return

Real rate of return adjusts for inflation, while nominal rate of return measures investment performance before that adjustment. Both can describe the same investment over the same dates; they answer different questions.

Subtracting inflation from nominal return is an approximation, not the exact calculation. In the example, 10% minus 4% gives 6%, compared with the exact formula's result of about 5.77%. The shortcut is closer when the rates are small, but the division formula works without relying on that approximation.

Common questions

Can the real rate of return be negative? Yes. If inflation exceeds your nominal investment return, purchasing power falls even when the investment gains dollars. A zero real return means the investment keeps pace with the inflation measure you use.

Do contributions count as investment returns? No. A deposit increases the account balance without showing that the investments earned anything. When money enters or leaves during the measurement period, use a return calculation that accounts for those cash flows before adjusting for inflation.

Does real return include fees and taxes? Not automatically. The inflation adjustment starts with whichever nominal return you supply. State whether that return is before or after fees and taxes so readers know which costs the real return reflects.

Which inflation rate should I use? Use a price measure relevant to the spending you want the investment to support, covering the same period as the return. A broad consumer-price measure is a benchmark, but your own spending mix can experience different price changes.

Go deeper

• Is my net worth growing if prices are rising? compares net worth snapshots in the same period's dollars.
• How to track net worth when your investments swing every day separates money you contribute from changes driven by investment markets.
• The Retirement calculator projects what your retirement savings could grow to, what that is worth in today's dollars, and the monthly income it could support.