NEW YORK -- Standard&Poor's CreditWire Feb. 22, 1999 – Standard&Poor's today assigned its single-'A'-minus/'A-1' rating to District of Columbia, D.C.'s $20.58 million revenue bonds series 1999, issued for American University. The bonds are expected to sell Feb. 25, 1999. The long-term rating reflects: -- Profitable, yet, tuition-dependent operations; -- Improvements in liquidity and endowment; and -- An adequate demand profile. Also factored into the rating is leadership stability since 1994 and sound financial planning. A higher rating is precluded by limited admissions flexibility, high student fee dependence, and only adequate liquidity. The short-term rating on the bonds is based on a standby purchase agreement provided by Westdeutsche Landesbank Girozentrale (West LB). Although West LB's short-term rating