5 Smart Investing Principles The slideshow presentation that you would like to view is too large for your current screen resolution. Click here to view to view the slideshow at full resolution. Launch Presentation » Share | Have A Question About This Topic? Name Email Address Question Thank you! Oops! 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. Why Medicare Should Be Part of Your Retirement Strategy How Medicare can address health care needs in your retirement strategy. Where Will Your Retirement Money Come From? Retirement income may come from a variety of sources. Here's an overview of the six main sources.