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. Related Content Required Reading: The Economic Report of the President The Economic Report of the President can help identify the forces driving — or dragging — the economy. The Anatomy of an Index The S&P 500 represents a large portion of the value of the U.S. equity market, it may be worth understanding. Mortgages in Retirement Explore the benefits and drawbacks to paying off your mortgage prior to retirement with this article.