SOUTH PORTLAND – Sales of existing single-family homes in Maine declined by 17.2 percent last month – from 1,247 units to 1,032 – compared with July 2007, the Maine Real Estate Information System reported Monday.

During the same period, the median sale price of homes dipped 3.5 percent, from $199,000 to $192,000.

In Penobscot County, 332 homes were sold between May 1 and July 31, down 24 percent from the 437 that sold during the same period in 2007.

In Aroostook County, 95 homes were sold during the May-through-July period, down 5.9 percent from the 101 that sold during the same period in 2007.

Washington County was the only Maine county to see an increase in the number of sales. A total of 18 homes were sold during the May-through-July period, up 50 percent from the 12 that sold during the same period in 2007.

During the May-through-July period, median sales prices were up 6.4 percent in Aroostook County, 3.8 percent in Waldo County and 15.2 percent in Washington County over the same period in 2007.