Rule of 72
Estimate how long it takes to double your investment
What do you want to calculate?
Typical returns: S&P 500 ~10%, Bonds ~5%, Savings ~2%
About the Rule of 72
The Rule of 72 is a simple formula to estimate the number of years required to double an investment at a given annual rate of return. Divide 72 by the interest rate to get an approximate doubling time. This rule is most accurate for interest rates between 6% and 10%.