The “shadow inventory” of bank-repossessed properties, as well as distressed mortgages facing foreclosure, will take nearly three years to clear at the current sales rate, according to a report from the credit rating agency Standard & Poor’s (S&P). The analysts add that during this period many servicers will likely shift their emphasis from mortgage modification to loan liquidation.

The “shadow inventory” of homes includes all delinquent loans and real-estate owned (REO) property that has not reached the market. REO property are foreclosed homes taken back by the bank for liquidation. As for the total amount of homes in the shadow inventory, Amherst Securities places the total at 7m. The Royal Bank of Scotland found 2.7m, and First American CoreLogic counted 1.7m.

S&P estimates the inventory to equal a 33-month supply of homes. Analysts added the estimate is actually conservative, as they did not assume homes not showing signs of distress would default and push the overhang of supply even further.

Furthermore, court delays, political pressure and servicing backlogs constricted the flow of foreclosures hitting the market to a trickle. These delinquent borrowers who have not received a foreclosure fuel the “rapidly” growing shadow inventory of properties, according to the report.

“Overall, it is our opinion that recent positive housing reports should not be construed as a sign that the distress in the residential housing market is abating, but rather should be attributed to the temporarily limited supply of homes on the market,” according to the report.

Another credit rating agency, Moody’s, showed that the underwhelming performance of the Home Affordable Modification Program (HAMP), which the US Treasury Department launched in March 2009 to give incentives to servicers for the modification of loans on the verge of foreclosure, will drive down housing prices another 8% from Q409 to the end of 2010.

According to the S&P report, homes are falling into serious delinquency faster than REO transactions are closing. The total balance of seriously delinquent loans reached well over $400bn through November 2009, while the balance of REO properties reached its peak in September 2008 and declined to $50bn. On average, $14.5bn of seriously delinquent loans or REO property liquidates each month. According to the report, it will take 29 months to clear this supply of homes: