DALLAS (S&P Global Ratings) Feb. 22, 2017--S&P Global Ratings corrected by raising the rating on Houston's series B-1 commercial paper (CP) notes to 'A-1+' from 'A-1'. The rating is based on the long-term underlying rating of the city's combined utility system. We affirmed our 'AA' rating on its working lien on July 26, 2016. The outlook on the long-term debt is stable. Liquidity support for the series B-1 notes is provided through Jan. 1, 2019, secured by a revolving credit agreement with Bank of America N.A. We understand that the revolving credit agreement supports up to $100 million in principal, and 270 days of interest at up to 10%. Barclays Capital LLC, Citigroup Global Markets Inc., and JP Morgan Securities