SAN DIEGO (AP) — Demand for more expensive properties lifted California home prices to a nearly two-year high in May as sales across all pricing categories showed healthy gains, a research firm said Thursday.

The median price for new and existing houses and condos reached $270,000 last month, up 8.4 percent from $249,000 in the same period last year and matching the highest level since June 2010, DataQuick said. The median price is still well below a peak of $484,000 in early 2007 but up from $221,000 in April 2009.

The median price has risen three straight months from year-ago levels.

The number of homes sold in May rose 17.6 percent from last year to 41,790, the highest tally for that month since 2006, the San Diego-based research firm said.

Foreclosed homes, which tend to sell at a discount, made up a smaller part of overall sales, lifting the median price. DataQuick said properties that had been foreclosed upon in the previous year accounted for 28.3 percent of existing-home sales, down from 35.3 percent a year earlier and 58.5 percent in February 2009.

The San Francisco Bay area's median sales price was $400,000, up 7.5 percent from $372,000 a year earlier, DataQuick said. The median is still well below a peak of $665,000 reached in 2007 but up from $290,000 in March 2009.

Sales in the nine-county Bay area soared 26.1 percent from last year to 8,810, with the most significant gains in pricier categories. Sales of homes between $400,000 and $800,000 jumped 26.2 percent, while homes below $300,000 rose a more modest 12.5 percent.

"It's not exactly a stampede, but people are starting to move off the housing market sidelines in numbers we haven't seen in quite a while. And it's not just first-time buyers and investors," said DataQuick President John Walsh.

The lowest-priced homes, particularly foreclosed properties, have long been driving sales in California, but the latest figures show that all pricing categories are drawing more interest from buyers.

DataQuick reported Wednesday that the median sales price in Southern California reached $295,000 in May, up 5.4 percent from $280,000 the same period last year. It marked the second straight month that the prices increased from a year earlier in the six-county region, following 13 straight year-on-year declines. It was also the highest since September 2010.

The number of homes sold in Southern California jumped 20.6 percent from last year to 22,192. More expensive coastal regions accounted for a larger part of overall sales.