NEW YORK (Standard&Poor's) March 13, 2012--Standard&Poor's Ratings Services has assigned its 'AA' rating to the City of San Antonio, Texas' electric and gas systems $521 million revenue bonds, taxable new series 2012. At the same time, Standard&Poor's affirmed its 'AA' rating on senior-lien parity debt, its 'AA-' rating on junior-lien bonds, and its 'A-1+' commercial paper rating on the city's electric and gas utility, known as CPS Energy. The outlook is stable. As of fiscal year-end 2012 (Jan. 31), the electric and gas utility had $4.7 billion of debt outstanding. "The rating reflects what we view as several strengths of CPS Energy, including a strong, growing economy; very competitive electricity rates; strong financial metrics;