Sales of existing homes were weaker in the Midwest than the national average in August, but the median price of homes held up better, the Associated Press reported.

Sales of existing homes in the Midwest fell nearly 18 percent in August from the year-ago period, more than the 15 percent decline nationally. Meanwhile, the median sales price in the region fell 5.6 percent to $168,000, compared with a 9.5 percent decline nationally to $203,100, according to the National Association of Realtors.

According to the Des Moines Area Association of Realtors, the average home price in Greater Des Moines fell about 1 percent, staying around $180,000, while the number of closed contracts dropped to 802, compared with 1,053 in August 2007.

The Midwest is starting to see the effects of a tightening credit market and falling home prices, with the biggest declines in median sales prices occurring in Detroit, Cleveland and Minneapolis. Detroit, which has faced a huge wave of foreclosures amid a sinking economy, has seen a 30 percent decline in median home prices in the past year, but sales fell only 2 percent, a sign that buyers are taking advantage of lower prices.

Nationally, the inventory of unsold homes fell 7 percent to 4.3 million from a record 4.6 million in July. However the 10.4-month supply of homes at the current sales pace is far from the five months of inventory that is more typical. Homeowners who don’t have to sell could also be keeping properties off the market, and thousands of foreclosed properties are tied up in courts.

The government’s takeover of mortgage giants Fannie Mae and Freddie Mac, along with a $700 billion plan to buy bad debt, including distressed mortgage securities, could help make it easier for home buyers to obtain a loan, which could boost the housing market.