The best retirement-savings vehicle is one that few have heard about: I bonds. They offer a risk-free yield of 9.62%, yet the amount of I bonds issued is only a small fraction of the total volume of bond issuance by the U.S. Treasury.  My guest today will explain that paradox. This is also the 300th episode of the Gaining Perspective podcast, and no guest would be more appropriate than Zvi Bodie. He has eloquently and persuasively made the case for the financial services industry to provide products that respond to the needs of everyday investors.