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 Should You Invest in Exchange Traded Funds? There are hundreds of ETFs available. Should you invest in them? Alternative Investments - Going Mainstream Alternative investments are going mainstream for accredited investors. It’s critical to sort through the complexity. Jane Bond: Infiltrating the Market Agent Jane Bond is on the case, cracking the code on bonds.