Of all the things you can learn about money –the rule of 72 should be at the top of your list.
The Rule of 72 is a shortcut to estimate the number of years required to double your money at a given annual rate of return. The rule states that you divide the rate, expressed as a percentage, into 72: Years required to double investment = 72 ÷ compound annual interest rate. For example, let’s say you can earn a 10% rate of return. How long will it take $1,000 to grow into $2,000?