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 From Boats to Brokers From the Dutch East India Company to Wall Street, the stock market has a long and storied history. How to Spend Smart to Improve Cash Flow Congratulations — your business is profitable! Have you considered how much of those profits to reinvest in your business? What Smart Investors Know Smart investors take the time to separate emotion from fact.