In certain sectors, it may not be possible to draw statistically significant conclusions regarding ratings differences because ratings several notches apart have historically similar probabilities of upgrades and downgrades. * There are significant differences in the frequency and direction of ratings changes between single- and multi-rated issues, particularly for those not rated AAA. Fitch and Moody's speculative grade ABS had more downgrades on their single-rated deals than on their multi-rated deals. Fitch and S&P speculative grade RMBS had fewer downgrades on their single-rated deals than on their multi-rated deals. S&P * S&P was more likely to initiate a downgrade in ABS than Fitch; S&P was more likely than Fitch or Moody's to initiate a downgrade in RMBS; Moody's and S&P were more likely than Fitch to initiate CDO downgrades, although there were comparatively few CDO observations.