The top credit ratings agencies, buffeted by severe criticism of their failed models, are tinkering with new schemes. At a minimum, they have to at least appear to be changing at a time like this. Moody's says it is pondering a raft of new options. Moody's has offered five proposals for public comment. It will accept opinions until February 29. An analysis will be issued within two to three months, according to the Financial Times. One idea is to have a more uniform rating scale--one might use numbers instead of letters (from AAA to C)--with the idea being that the ranking holds for all assets. There would still be 21 credit ratings. The same numerical rating would imply the same level of creditworthiness for a CDO as a corporate bond. Another option would be to keep the same letter system but add something that would identify bond asset classes.  

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