Home prices fell in half of U.S. cities in the third quarter as banks stepped up repossessions of properties in default.

The median price of a single-family home dropped in 76 of 155 metropolitan areas measured, the National Association of Realtors said in a report today. Prices in Ocala, Florida, slumped 20 percent for the biggest decline. Palm Bay, Florida, and Tucson, Arizona, followed with a 15 percent slide. The median U.S. price fell 0.2 percent to $177,900.

The U.S. housing market is struggling as lenders seize a record number of properties and unemployment hovers near a 26- year high. Banks took over 288,345 homes in period covered by the Realtors report, up 22 percent from a year earlier, according to RealtyTrac Inc., a data firm in Irvine, California. Foreclosures boost the supply of available homes and reduce prices because they sell at a discount.

“The bottom has proven to be quite elusive,” said Stan Humphries, chief economist of data firm Zillow.com in Seattle. “There could be another 5 percent coming off the national market” as prices decline further, he said.

The median price of a single-family home in the New York metropolitan area climbed 2.8 percent in the third quarter. The Edison, New Jersey, region had a 3.5 percent gain and prices in the Boston metropolitan area rose 5.3 percent, the report said.

The best-performing markets included Burlington, Vermont, with a price increase of 18 percent; Elmira, New York, up 17 percent; and Dallas-Fort Worth, which gained 14 percent.

In a separate report today, the Realtors group said U.S. sales tumbled 25 percent to a 4.16 million seasonally adjusted annual pace in the third quarter from the previous three months. The pace was 21 percent below the 5.28 million rate of the year- earlier period.

The U.S. homeownership rate remained at a 10-year low of 66.9 percent in the third quarter, the U.S. Census Bureau said in a Nov. 2 report.