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 Global and International Funds Investors seeking world investments can choose between global and international funds. What's the difference? The ABCs of Zero Coupon Bonds Understanding some basic concepts may help you assess whether zero-coupon bonds have a place in your portfolio. Impact of Taxes and Inflation Estimate the potential impact taxes and inflation can have on the purchasing power of an investment.