California's housing-market slump showed hints of improvement in March, with sales of existing single-family homes increasing 64% from the prior-year period and median home prices rising month-to-month for the first time since August 2007, according to a trade group report.

California's inventory of unsold homes in March fell to a three-year low of five months, according to a report released Monday by the California Association of Realtors. That compares with 12.2 months of inventory the group reported for March 2008.

The state saw sales of 522,980 existing single-family homes in March, compared with 319,290 in the year-earlier period, the report said. Home prices remained sharply down from a year ago: The March median price of $253,000 was up from $247,590 in February 2009 but down 39% from March 2008 levels.

Stimulus efforts helped the state's home sales in the month, said Delores Conway, a professor at the University of Southern California's Marshall School of Business. Some Californians benefited from about $8,000 in credit for first-time home buyers from the federal economic-stimulus plan, and some from an additional $10,000 credit from a state stimulus measure. Depressed prices of houses are luring first-time buyers, she added.

But the March improvements are partly statistical, Ms. Conway added, because the number of sales in March 2008 was especially low. And California's unemployment rate, one of the nation's highest at 11.2%, may also delay any housing-market recovery by resulting in more foreclosures, she said.

Another concern is the recent ending of moratoriums on foreclosures by Fannie Mae, Freddie Mac and some big lenders. That is expected to lead to a new increase in foreclosures in California and elsewhere over the next few months.

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