In that February ratings action, Moody's downgraded senior investment grade bonds, including junior AAA-rated classes, four to five notches, compared to five or six notches for low investment-grade and speculative-grade bonds. Mezzanine and "super duper" AAA CMBS were left untouched in February, although Moody's on Friday warned that mezz AAA classes, "while stable for now, are very sensitive to further increases in expected loss."

Since February, "property prices have continued their march downward," according to Friday's report. As GlobeSt.com reported earlier his month, the Moody's/REAL National All Property Type Aggregate Index for March, released in late May, showed a year-over-year decline of 20.8% from March 2008. In the report released on Friday, Moody's predicts a peak-to-trough price decline of more than 30%, along with capitalization rates trending higher for the next several quarters.

However, the report notes, "despite the grim prognosis for property values, it is important to repeat the point made in the February report announcing our ratings sweep: that property value is primarily a concern at loan maturity." With the bulk of CMBS maturities not due to occur until 2016 or 2017, "the maturity profile of the universe of CMBS loans is relatively benign."