Performance on Alternative-A loans behind residential mortgage-backed securities issued in 2005, 2006 and 2007 continues to deteriorate, with the biggest increase occurring with the 2007 vintage.

Total delinquency on 2005 vintage Alt has gone from 11.66 percent in February to 15.65 percent in July, Standard and Poor's Ratings Services said in a report released today. Foreclosures on the 2005 vintage have gone from 3.26 percent to 5.35 percent during that same period. Cumulative losses more than doubled from 0.20 percent to 0.50 percent from February to July.

Deals issued by Impac in 2005 are among the worst performers among the top 10 issuers, with total delinquency of 27.61 percent, foreclosures at 10.29 percent and cumulative losses of 1.23 percent as of July 25.

On the 2006 vintage, total delinquency has gone from 15.17 percent in February to 21.45 percent in July, while foreclosures went from 4.56 percent to 7.60 percent. Cumulative losses climbed from 0.19 to 0.75 percent.

Bear Stearns deals performed the worst among the top 10 issuers in 2006, with total delinquencies of 27.52 percent, foreclosures at 9.39 percent and cumulative losses of 1.24 percent.

Total delinquency on the 2007 vintage has risen from 9.08 percent to 14.56 percent -- more than either of the two prior years. Foreclosures have gone from 2.92 percent in February to 5.46 percent in July. Cumulative losses skyrocketed from 0.03 percent to 0.29 percent.

Among last year's top 10 issuers, RFC had the highest total delinquency, at 18.89 percent, while American Home had the worst foreclosure rate, at 8.52 percent, and the highest cumulative losses, at 1.22 percent.

At 18 months of seasoning, the 2007 vintage is performing the worst since 2002 with total delinquency, trailed by the 2006 vintage and the 2004 vintage.