The Rule of 72 Do you know how long it may take for your investments to double in value? The Rule of 72 is a quick way to figure it out. Share | Related Content 16 Wall Street Cliches in 60 Seconds Pundits say a lot of things about the markets. Let's see if you can keep up. The Investment Risk No One’s Ever Heard Of You face a risk for which the market does not compensate you, that can not be easily reduced through diversification. Keys to Investing for Retirement There are some key concepts to understand when investing for retirement.