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 When Markets React When markets shift, experienced investors stick to their strategy. The Utility of Sector Investing Successful sector investing is dependent upon an accurate analysis about when to rotate in and out. 5 Smart Investing Principles Principles that can help create a portfolio designed to pursue investment goals.