Interest Rates: How Low Can They Go? The question used to be, “How low can interest rates go?” Now it's, “How long can rates remain at their historic low levels?” Share | Related Content It Was the Best of Times, It Was the Worst of Times All about how missing the best market days (or the worst!) might affect your portfolio. The Business Cycle Understanding the economy's cycles can help put current business conditions in better perspective. Keys to Investing for Retirement There are some key concepts to understand when investing for retirement.