Mortgages classified as subprime provide collateral for $800 billion in securities. At the end of August, about $46 billion in subprime loans, representing 225,000 homes, had defaulted, according to Credit Suisse Group. The number will more than triple to $143 billion by the middle of 2009, said the bank. Total subprime loan defaults will top out at about $270 billion, or 1.52 million homes, in 2010 or later. Teaser rates apparently caused many of the problems. Mortgage-backed securities and collateralized debt obligations containing those securities are falling in price and will continue to slide due to falling home prices, defaults, and general distrust. The issue is not strictly a subprime issue. Here is why: