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 The Junk Drawer Approach to Investing It's easy to let investments accumulate like old receipts in a junk drawer. The Great Debate Continues: Active vs. Passive In investments, one great debate asks the question, “Active or Passive Investing: Which Is Better?” Keys to Investing for Retirement There are some key concepts to understand when investing for retirement.