Standard&Poor's Ratings Services assigned its 'AA-' standard long-term rating, and positive outlook, to Atlanta Downtown Development Authority, Ga.'s series 2006A and 2006B revenue bonds, issued for Atlanta, and affirmed its 'AA-' standard long-term rating and Standard&Poor's underlying rating (SPUR), and positive outlook, on Atlanta's preexisting GO debt. The bonds are secured by an assignment of rights to rental payments made by the city under an intergovernmental agreement between the city and authority. The city's full faith and credit pledge secures its obligation to make rental payments. The ratings reflect the city's 'AA-' GO rating and its: Diversified regional economic base, which is experiencing a slow recovery from the recession; Sound reserves despite planned fund balance reductions