...OVERVIEW + We affirmed our ratings on 21 Citiseries class A notes from Citibank Credit Card Issuance Trust. + The affirmations follow Citibank's reduction in the required subordination amount of the series 2009 collateral certificate from 7.66865% to 3.84764%. TORONTO (S&P Global Ratings) Nov. 3, 2017--S&P Global Ratings today affirmed its ratings on 21 Citiseries class A notes issued by Citibank Credit Card Issuance Trust (CCCIT). We also discontinued our rating on the Citiseries class 2007-A9 notes because the notes were repaid in full on the Oct. 17, 2017, distribution date (see list). The affirmations reflect our view of the transactions' revised credit support, pool characteristics, payment and legal structures, as well as a review of our base-case assumptions and stresses to the key variables (yield, charge-off rate, and payment rate) that we use when modeling and rating credit card asset-backed securities (ABS) based on the collateral's performance trends and economic outlook. On...