We revised the outlook on The United States of America sovereign credit rating to negative from stable. We have revised our outlook to negative from stable and affirmed our 'AAA' long-term counterparty credit rating on National Securities Clearing Corp. The rating on the NSCC is constrained by the sovereign credit rating as NSCC's business activity and collateral on deposit are highly concentrated in the U.S. On April 19, 2011, Standard&Poor's Ratings Services revised its outlook on New York-based National Securities Clearing Corp. (NSCC) to negative from stable, following the outlook revision to negative from stable on the long-term sovereign credit rating on the United States of America (AAA/Negative/A-1+; see United States Of America ?AAA/A-1+? Rating Affirmed; Outlook Revised
