Rule of 72

The rule of 72: divide 72 by your interest rate to estimate years to double. 72 ÷ 7% ≈ 10.3 years.

RateYears to double
3%24.0
4%18.0
5%14.4
6%12.0
7%10.3
8%9.0
10%7.2
12%6.0
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