Sales of existing homes, coops and condos rose 6.8% in March from February to an adjusted annual rate of 5.35 million, 16.1% ahead of the pace in March 2009, the National Association of Realtors reported Thursday. The increase, which was evident across all regions, was in line with what Wall Street was expecting.

The Realtors attributed the increase to improving market conditions and the federal home buyer tax credit, which is set to expire at the end of April for purchases and the end of June for closings.

The median price for all housing types was relatively flat with March, 2009 at $170,700, a 0.4% gain. Distressed homes accounted for 35% of sales last month, unchanged from February. First-time buyers purchased 44% of homes in March, up from 42% in February; investors accounted for 19% of transactions in March, flat with February; all-cash sales remained elevated at 27% in March, the same as February.

Inventory, was up1.5% to 3.58 million homes for sale, an 8.0-month supply, down from an 8.5-month supply in February. Raw unsold inventory was 1.8% below March, 2009 and 21.7% below the peak of 4.58 million in July 2008.

Single-family home sales were up 7.3% to a rate of 4.68 million in March from 4.36 million in February, 13.3% above the pace of March, 2009. The median existing single-family home price was $170,700 in March, up 0.6 percent from March 2009 and up from $163,900 in February. Single-family inventory rose 1.4% from February to 3 million but was down 2% from March of last year. Months-supply of single-family homes was down 6.1% to 7.7.

Single-family median prices rose in 14 out of 20 metropolitan statistical areas reported in March in comparison with a year earlier. Among the best performers were San Diego, with a 20.4% median price jump to $393,600; St.Louis, up 19.8% to $129,300; Boston, up 13.9% to $329,800; Phoenix, up 13.3% to $144,500; and Pittsburgh, up 13.1% to $122,900.

Regionally, existing-home sales in the Northeast increased 6% to an annual level of 890,000 in March, 25.4% higher than a year ago, with the median price up 8.9% to $249,800. The Midwest rose 7.2% to a pace of 1.19 million, 15.5% ahead of March 2009, with the median price up 0.2% to $139,300.The South was up 7.1% to 1.97 million, 13.9% higher than a year before, with the median price up 5.2% to $154,800. The West gained 6.6% to 1.3 million, 14% above March 2009, but the median price fell 7.9% to $209,400.

"Sales have been above year-ago levels for nine straight months, and inventory has trended down from year-ago levels for 20 months running," said Lawrence Yun, chief economist for the Realtors. "The home buyer tax credit has been a resounding success as these underlying trends point to a broad stabilization in home prices."