by Calculated Risk on 10/17/2007 01:07:00 PM

S&P: Review Of 1H07 US RMBS Yields Downgrades, Watch Placement (hat tip Brian)

Oct. 17, 2007--Standard & Poor's Ratings Services today lowered its ratings on 1,713 classes of U.S. RMBS backed by first-lien subprime mortgage loans, first-lien Alternative-A (Alt-A) mortgage loans, and closed-end second-lien mortgage loans issued from Jan. 1, 2007, through June 30, 2007. These classes are from 136 subprime transactions, 128 Alt-A transactions, and 19 closed-end second-lien transactions. The downgraded classes represent approximately $23.35 billion of original par amount, which is 6.28% of the $371.9 billion original par amount of these three types of U.S. RMBS rated by Standard & Poor's between Jan. 1, 2007, and June 30, 2007, and 4.71% of the approximately $495 billion original par amount of all
U.S. RMBS rated during this period.

In addition, we placed the ratings on 646 other classes from 109 transactions backed by U.S. RMBS first-lien subprime mortgage loans and U.S. RMBS first-lien Alt-A mortgage loans issued during the same period on CreditWatch with negative implications.