 Both Fitch Ratings and Moody's, designated like S&P as nationally recognized statistical rating organizations (NRSRO) by the U.S. Securities and Exchange Commission (SEC), retained the U.S.'s triple-A rating.Moody's, however, changed its outlook to negative on June 2, 2011, and Fitch changed its outlook to negative on November 28, 2011.A credit rating is issued by a credit rating agency (CRA).