The Rule of 115 follows the Rule of 72. If doubling your money isn’t good enough, the Rule of 115 will show you how long it will take to triple your money. It’s as simple as dividing your interest rate by 115. The quotient is the amount of time it will take you to triple your money.

For example, if your money earns an 8 percent interest rate, it will triple in 14 years (115 divided by 8 equals 14.3).

If your money earns a 5 percent interest rate, it will triple in 23 years (115 divided by 5 equals 23).

Note that tripling your money is easier – in some respects – than doubling your money. If you’re earning a 5 percent interest rate, you’ll spend 14-and-a-half years trying to double it, but only an additional 9 years tripling it.
//The Balance

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