Good question, Bill. Why the big demand for mortgage-backed securities (MBS)? Several reasons for that. (1) There is a huge amount of pension money out there looking for investment vehicles. (2) They tend to go 50-50 stocks and bonds. With stocks high and not doing so well for the past 8 years, they are quite happy to find something that yields 6%, like a mortgage security. (3) F&F made guarantees on many of these securities. (4) The MBS securities were often packaged up in tranches to satisfy different risk appetites of various investors. This broadened the market considerably. (5) The market went international. (6) The pension fund industry has serious agency problems. The management is often removed several steps from the investor, with a company plan in between. Thus, they do not do the due diligence they should. (7) A well-oiled machine developed for placing these issues.