Rule of 72


Take the expected interest and divide it into 72. That is an easy way to calculate the number of years it takes to double your money.

Watch The Results - At 8% Each Dollar Multiplies By 2,199 Times in 100 Years

Invest $100 at 7%...8%...9% compounded for 25, 50, 75 and 100 years

Years Compound @ 7% Compound @ 8% Compound @ 9%

25 Years $543 $685 $862

50 Years $2,946 $4,690 $11,414

75 Years $15,988 $32,120 $64,119

100 Years $86,772 $219,976 $552,904

Invest $10,000 at 7%...8%...9% compounded for 25, 50 and 100 years

Years Compound @ 7% Compound @ 8% Compound @ 9%

25 Years $54,274 $68,485 $86,230

50 Years $294,570 $469,014 $1,141,400

75 Years $1,598,760 $3,210,000 $6,411,909

100 Years $8,677,160 $21,997,612 $55,290,407