NEW YORK (Standard&Poor's CreditWire) Feb. 27, 2001—Standard&Poor's maintained the ratings on Firstar Corp. and U.S. Bancorp following the completion today of the merger between the two. The ratings were affirmed on Oct. 4, 2000. The name of the surviving entity is U.S. Bancorp and its counterparty and senior unsecured debt ratings are 'A'. At the same time, the ratings on the former U.S. Bancorp were withdrawn. The outlook is considered stable. Now a $160 billion financial services company headquartered in Minneapolis, Minn., U.S. Bancorp's empire spans the nation from Oregon to Tennessee. The company will operate 2,200 branches in 24 states and will have an ATM network of 7,700, placing it in the top-fifth spot on