NY -- Standard&Poor's CreditWire 3/11/98 – Standard&Poor's today raised its rating on the District of Columbia's $900 million general obligation bonds to double-'B' from single-`B', and certificates of participation to double-'B'-minus from single-'B'-minus. Standard&Poor's also raised its rating on the District of Columbia Redevelopment Land Agency's sports arena special tax revenue bonds series 1996 to double-'B' from single-`B'. These ratings are removed from CreditWatch, where they were placed Aug. 8, 1997. The outlook is positive. The upgrade is based on improved financial and administrative factors resulting largely from federal legislation affecting the district. The higher rating will be assigned to the G.O. bond issue to be sold the week of March 30. The ratings