Home prices in the U.S. rose in the second quarter of 2010, according to the Federal Housing Finance Agency (FHFA).

The regulator’s purchase-only house price index (HPI) is calculated using sales price data from Fannie Mae- and Freddie Mac-acquired mortgages, and last quarter was the first time since Q2 2007 that the HPI posted a quarterly increase.

The index was 0.9 percent higher on a seasonally adjusted basis in the second quarter than in the first quarter of 2010. The unadjusted national increase was 2.6 percent. However, on a year-over-year basis, prices are still depressed, down 1.6 percent.

FHFA’s seasonally adjusted monthly index for June was 0.3 percent below its May value, offsetting some of the price increases in the prior months. The monthly increase for the April-to-May period was revised downward to 0.4 percent, from an initial estimate of 0.5 percent.

FHFA noted that while the national, purchase-only house price index fell 1.6 percent from the second quarter of 2009 to the second quarter of 2010, prices of other goods and services rose 3.0 percent over the same period. Accordingly, the inflation-adjusted price of homes dropped about 4.4 percent over the latest year, the agency explained.

As measured with purchase-only data, annual price declines were greatest in the Phoenix-Mesa-Glendale, Arizona area, which saw sales prices drop 5.5 percent between the second quarters of 2009 and 2010.

Prices held up best in the Oakland-Fremont-Hayward, California metro, where prices rose 9.9 percent over the one-year period.

FHFA’s all-transactions house price index, which includes data from mortgages used for both home purchases and refinancings, declined over the latest quarter. The index fell 0.5 percent in the latest quarter and 4.9 percent over the four-quarter period.

FHFA’s purchase-only and all-transactions HPI track average house price changes in repeat sales or refinancings of the same single-family properties.

The purchase-only index is based on more than 6 million repeat sales transactions, while the all-transactions index includes more than 40 million repeat transactions. Both indexes are based on data obtained from Fannie Mae and Freddie Mac for mortgages originated over the past 35 years.