The 'AAA / A-1+' rating on San Francisco City and County, Calif.'s multifamily housing revenue refunding bonds (City Heights Apartments), series 1997 A has been affirmed. The bonds are backed by a mortgage loan that is secured by a Fannie Mae collateral agreement, which is 'AAA' eligible under Standard&Poor's Rating Services rating criteria. The 'AAA' component of the rating represents the likelihood that bondholders will receive debt service payments. The 'A-1+' component of the rating represents the likelihood of payment for mandatory and optional tenders. Other rating factors include: The sufficiency of revenues from mortgage debt service payments and investment earnings to pay full and timely debt service on the bonds until maturity, A fully funded interest reserve
