The good news is that more than half of Illinois counties saw gains in median home sale prices during the third quarter. The bad news is that most of the Chicago area played no part in that good news.

In Cook County, the median selling price fell 14.3 percent during the three months that ended in September, a combination of a 16.3 percent price decline in condos and a 7.9 percent drop in single-family home prices, according to data released Wednesday by the Illinois Association of Realtors. Other counties that experienced price declines were Kane, where the median price fell 13.3 percent; Kendall, down 8.3 percent; and McHenry, down 3.7 percent.

Meanwhile, the median selling price rose 0.6 percent in DuPage County; 4.2 percent in Lake County; and showed no change in Will County.

The real estate trade group blamed a 24.9 percent decline in third-quarter sales of existing homes on the expiration of a homebuyer tax credit, which may have caused some buyers to speed their home purchases. During the quarter, 24,628 Illinois homes were sold, compared with 32,776 sales in the same period a year ago.

Home sales dropped 22.4 percent in the Chicago area and 23.1 percent within the city of Chicago.