The median price of single-family homes in Chicago jumped 9.5 percent in May over the same period in 2015, but condo prices rose only 1.1 percent, according to data released Wednesday by the Illinois Association of Realtors.

The average time on market was 40 days, down from 46 in 2015.

Meanwhile, the number of home sales across the nine-county metropolitan area rose 7.5 percent over the previous year. The median price increased 6.1 percent, to $234,000, since last year, though the rate of growth is down from a 7.2 percent increase reported in May 2015.

The increase in regional sales numbers was propelled by purchases of foreclosed properties, says economist Geoffrey J.D. Hewings, director of the Regional Economics Applications Laboratory at the University of Illinois.

The rest of the year should see only modest increases in sales, Hewings predicts. “A lot of people are going to be very leery about making a major commitment,” he says, citing continuing uncertainty brought on by the state’s budget impasse and the upcoming presidential elections.

Sales of foreclosed properties, which account for slightly less than 20 percent of the overall market, rose 12 percent compared to a year ago, while sales of all other homes were up only 1 percent. “There are a lot of pretty attractive houses in the foreclosure inventory," Hewings says. "These are not trash properties."

The median sale price for a foreclosed home approaches $160,000. That compares to a median sales price for all Chicago area homes of $234,500 in May, the Illinois Association of Realtors reported Wednesday. Hewings says he did not have data to determine what percentage of foreclosed sales can be attributed to flippers as opposed to new homeowners.

Looking at overall market conditions, “Realtors tell me right now one of the biggest problems is lack of inventory,” Hewings says.

Many homeowners remain underwater from the recession, meaning they owe more on their mortgages than their homes could sell for. A recent report from Zillow estimated that 20.3 percent of Chicago area homeowners are underwater. Those owners are waiting until prices rise higher before listing their homes, contributing to the tight inventory of homes currently for sale in the Chicago area, he says.

McHenry County saw the largest May sales price gain of any county in the Chicago area, with its median sale price up 13 percent over last May. The median sale price in Cook County rose only 4.3 percent.