Home sales in San Diego County surpassed 4,000 for the first time in nearly two years in April, as the median sales price continued to rise over the year.

Real-estate tracker CoreLogic reported Tuesday that the median home price for a property sold last month was $455,000, up 4.6 percent annually.

“The market’s robust,” said Mark Goldman, a loan officer and real-estate lecturer at San Diego State University. “There is a lot of pent up demand, inventory has been very sparse, so it’s a sellers market right now, which is odd because there’s not a lot of price pressure upward.”

Over the last six months, the pace of home price appreciation has oscillated between 3.6 percent to 7.4 percent. That compares to 20 percent price growth in August 2013, the last time 4,000 properties changed hands – a time marked by investors fixing and flipping homes repossessed after the market crashed.

Still, Goldman said a lack of supply has been holding back the market because people who want to sell their homes can’t always find another for a trade up. In April, there were 6,386 active listings of resale homes, the San Diego Association of Realtors reports. That represents less than two months of supply, whereas analysts would like to see triple that amount in a normal market.

CoreLogic analyst Andrew LePage said consumers face many hurdles in the market face.

“Many buyers still face credit and affordability hurdles, and the inventory of homes for sale remains relatively tight in many markets. New home construction is still well below historically normal levels, too,” he said.

Interest rates fell in April to an average 3.67 percent for a 30-year-fixed mortgage, down from 4.34 percent in April 2014, Freddie Mac reports.

The median sale price was flat between March and April, which is subject to seasonal factors. Sales, however, rose 17 percent over the month.

Median home prices rose 10 percent annually in Los Angeles to $485,000, and 4.32 percent to $600,000 in Orange County.