Attention investors: The D.C. Office of the Chief Financial Officer has set up a new web site, www.buyDCbonds.com, in order to offer approximately $270 million in income tax-backed bonds for sale on August 18 through 19. The impending bonds offer comes at the same time that CFO Natwar Gandhi announced today that the city has retained its high marks from all three ratings agencies: Standard & Poor’s once again gave D.C. a AAA rating, Moody’s Investors Service’s assigned a Aa2 rating, and Fitch Ratings a AA designation. In a memo to D.C. Mayor Adrian Fenty, D.C. Council Chair Vincent Gray, and D.C. Council Finance Committee Chair Jack Evans (Ward 2), Gandhi also announced that all three rating services have given the bonds a “stable” ratings outlook. “I must emphasize that the affirmed ratings and stable outlooks are particularly commendable given the widespread strain in the current national economy. Many other states and local governments have experienced downgrades including California and Michigan, or a change in outlook to “negative” as the Washington Post reported about New Jersey yesterday,” Gandhi wrote in the memo.