Houses sold faster and at a lower cost in August compared with July numbers, the Des Moines Area Association of Realtors said today. Houses sold last month had been on the market an average 77 days, compared with 83 in July. "At 77 days on market, houses are selling a full three weeks faster than a year ago," Larry Pickering, president of the real estate association, said in a news release. The median sale price was $167,450, compared with $172,000 in July. Pending sales also dropped in August to 970 from 1,141 the previous month. The market continued to outpace year-ago numbers, with sales up 19 percent, pending sales up 8 percent and median sale price up 4 percent.