NEW YORK (Standard&Poor's) Dec. 5, 2014--Standard&Poor's Ratings Services has assigned its 'A' rating to the City of Austin, Texas's airport system revenue bonds, series 2014. At the same time, Standard&Poor's affirmed the 'A' rating on the city's first-lien airport bonds. The outlook is stable. "We believe Austin-Bergstrom International Airport has a strong origin and destination market, at 95% of enplanements, and good diversity of carriers, which are credit strengths," said Standard&Poor's credit analyst Peter Murphy. The airport's five-year capital improvement program beginning in fiscal 2014 totals $529 million, and calls for large debt issuances in 2014 and 2016. Bond proceeds will fund projects in the plan, including terminal expansion, parking, and airfield