NEW YORK (Standard&Poor's CreditWire) Oct. 12, 1999-- Standard&Poor's today assigned its triple-'A'/'A-1'-plus rating to Washington State Housing Finance Commission's $18.76 million variable-rate multifamily housing refunding revenue bonds (Avalon Ridge Apartments project) series 1999. The bonds are expected to sell Oct. 14, 1999. The rating on the commission's bonds reflects: -- Extremely strong credit enhancement of the mortgage backing the bonds through a Fannie Mae collateral agreement, and -- Triple-'A' rated investments. Upon bond closing, Fannie Mae will provide a direct-pay credit enhancement facility. The credit facility is direct pay through which Fannie Mae will make all regularly scheduled payments of principal and interest due on the mortgage. Under this structure, the trustee is instructed to draw