From Boats to Brokers From the Dutch East India Company to Wall Street, the stock market has a long and storied history. Share | Related Content 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. The Business Cycle Understanding the economy's cycles can help put current business conditions in better perspective. Saving for College This calculator can help you estimate how much you should be saving for college.