USA: Moody’s assigns A1 rating to Miami-Dade County transit system USD777.7 sales surtax revenue bonds 2009 September 9, 2009 | North America News Moody's investors’ service has assigned an A1 rating and stable outlook to the USD777.7 million sales surtax revenue bonds of Miami-Dade County transit system (MDT). The rating reflect... This content is available to only subscribers. Username or E-mail Password Remember Me Forgot Password