Prices for homes sold that were financed by Fannie Mae and Freddie Mac rose 0.4% from April to May on a seasonally adjusted basis, according to the Federal Housing Finance Agency's monthly House Price Index, released Thursday.

The previously reported 0.8% increase reported for April, however, was revised downward to a 0.2% increase.

For the 12 months ending in May, prices on houses financed by conforming loans fell 6.3%. The HPI was 19.6% below its April 2007 peak and roughly the same as its January 2004 level.

The FHFA monthly index is calculated using purchase prices of houses backing mortgages that have been sold to or guaranteed by Fannie Mae or Freddie Mac.

For the nine Census Divisions, seasonally adjusted monthly price changes from April to May ranged from -1.0 percent in the West South Central Division to +2.0 percent in the Mountain Division. The only other region to lose value month-to-month was the Middle Atlantic, which was down 0.8%.

Among other regions in May, the Pacific was flat, the West North Central up 1%, the East North Central up 0.5%, the East South Central up 1.3%, New England up 0.2% and the South Atlantic up 0.9%.

Compared to last may, the Pacific was down 9.9%, the Mountain down 9.2%, the West North Central down 5.9%, the West South Central down 3.4%, the East North Central down 4.4%, the East South Central down 4.4%, New England down 2.6%, the Middle Atlantic down 3.9% and the South Atlantic down 7.7%.

New England held the top spot in terms of value retention as measured by the HPI with a reading of 204, followed closely by the Mountain region at 202and the Middle Atlantic at 198.8. Among other regions, the indices stood at 172 for the Pacific, 191.9 for the West North Central, 192.8 for the West South Central, 160.1 for the East North Central, 182.3 for the East South Central and 177.7 for the South Atlantic. The U.S. index was at 181.8.

An index reading of 100 is the baseline purchase-only price in January, 1991.