Today's rating actions reflect Fitch's analysis of expected default and loss from the collateral pool in addition to cash flow analysis of each class. The average updated expected collateral losses as a percentage of the original pool balance for the 2005, 2006 and 2007 vintages are 17%, 39% and 47%, respectively. As a percentage of the remaining pool balances, the average expected losses for the three vintages are 45%, 59% and 55%.
The updated expected collateral losses incorporate performance trends since the last rating revisions which relied on September 2008 remittance data. The projected losses also reflect an assumption that from the first quarter of 2009, home prices will fall an additional 12.5% nationally and 36% in California, with home prices not exhibiting stability until the second half of 2010.