NEW YORK (Standard&Poor's) Aug. 11, 2008--Standard&Poor's Ratings Services assigned its 'A+' standard long-term rating, and stable outlook, to the District of Columbia's series 2008E and 2008F $480.8 million general obligation (GO) and GO refunding bonds. Standard&Poor's also affirmed its 'A+' standard long-term rating and underlying rating (SPUR), with a stable outlook, on the district's existing GO debt and 'A' standard long-term rating and SPUR, with a stable outlook, on the district's existing certificates of participation. The 'A+' rating reflects the district's healthy and diverse economy, anchored by the federal government, military contractors, services, and tourism, as well as its role as a regional employment center; sizable and growing property tax base that experienced strong