Prices for homes with mortgage backed by Fannie Mae and Freddie Mac in April rose for the first time since May of last year, when the federal home-buyer tax credit was still in effect, the Federal Housing Finance Agency reported Wednesday.

Prices rose 0.8% on a seasonally adjusted basis from March to April, according to the monthly House Price Index from a downwardly revised March estimate of 0.4%, which was originally reported as a 0.3% decline. It was the first increase in the index in a year and beat handily Wall Street expectations of a drop of 0.2%. Home builder stocks surged on the news.

FHFA said house prices year-to-date were down 5.7% at May's end with the U.S. index 19.3% below its April 2007 peak, putting values of homes covered by conventional mortgages at values roughly equal to shoe of January 2004.

Month-to-month gains were reported in six of the nine census divisions, led by a 2.2% gain in New England to an index of 203.5, 1.7% behind April, 2010.In terms of the overall index, New England house prices have held more value than any other region (an index of 100 equals value in January, 1991). The West South Central was close behind with a gain of 2.1% to an index of 197.2, 0.7% below April last year, followed by the East South Central (up 1.8% to 181.9 and down 3.7% year-over year), the East North Central (up 1.4% to 160.7 and down 5.4% year-over-year), the Middle Atlantic (up 1.3% to200.8 and down 2.5% from last April) and the Pacific (up 1% to 174.4, 7.7% off the price of the same month last year).

The biggest decline came in the Mountain division, which posed a 1.3% drop from March to and index of 200, down 10.9% from April, 2010. The West North Central dropped 0.6% to an index of 190.9, down 6.3% from a year earlier. The South Atlantic dropped 0.2% to 176.4, 8.6% behind April of last year.