Standard&Poor's Ratings Services confirmed its 'A-1+' rating on San Francisco City&County Airport Commission's (San Francisco International Airport) series A-3, B-3, and C-3 subordinate commercial paper notes, due to the bank facility being extended to May 19, 2017. The rating is based on the short-term rating on the letter of credit provider, Royal Bank of Canada. Criteria: Methodology And Assumptions: Approach To Evaluating Letter Of Credit-Supported Debt, July 6, 2009