The parameters used for this market analysis were:  Upper Darby, PA, 3 bedroom, Row and semi detached, with age of 50 to 70.  Data was gathered from Trend MLS.  The resulting graphs (below) tabulate trends (in rolling three month increments) for 1,116 sales that closed during the period from 11/1/2007 to 1/31/2011 as well as 127 current active listings. 

Three Month Median Value Graph:  Represents the trend in median values.

Three Month Median Close to List Price: Represents the trend in median sales to list price ratio.

Three Month Median DOM:  Represents the trend in median days on market (DOM).