The rule of 72 is a quick mental calculation you can use to calculate the years or compounding investment returns % to double a sum of money.
Calculate Years to Double Your Money at 8% Compounding Returns
Years to Double Your Money
= 72 / 8
= 9 years
Calculate Investment Returns % to Double Your Money over 3 years
Compounding Investment Returns %
= 72 / 3
This formula is useful for calculating either time or rate of returns to double your money.