You can track how long it takes to double your investment if you deposit money at a specific interest rate. For interest rates that fall between the rates in the chart, remember that the time will fall in between also.

Interest Rate Compounded Quarterly Amount of Time Needed to Double
2% ª 34.7 years
3% ª 23.2 years
4% ª 17.4 years
5% ª 13.9 years
6% ª 11.6 years
7% ª 10.0 years
8% ª 8.8 years
9% ª 7.8 years
10% ª 7.0 years
11% ª 6.4 years
12% ª 5.9 years
13% ª 5.4 years
14% ª 5.0 years
15% ª 4.7 years