Here is the Olney Area (Olney, Brookeville, Brinklow, Ashton, and Sandy Spring) supply and demand chart for April 2008. The Red lines are the active homes, blue under contract, and green are sold. The absorption rate is determined by the number of homes on the market and the number of homes selling that month.
We actually saw the absorption rates climb over May 07 numbers. That is a great sign of a healthy real estate market.
May 2008 14.2% absorption rate
May 2007 12.4% absorption rate
May 2006 19.9% absorption rate