SAN FRANCISCO - DECEMBER 28:  A sign is seen in front of a home for sale December 28, 2006 in San Francisco. Existing homes reportedly inched  up 0.6 percent in November as home prices continued a downward slide for the fourth consecutive month. The median home price for an existing home in the United States dipped to $218,000, down 3.1 percent comparing to the same month one year ago. Getty Images logo Getty Images 35 months ago

SAN FRANCISCO - DECEMBER 28: A sign is seen in front of a home for sale December 28, 2006 in San Francisco. Existing homes reportedly inched up 0.6 percent in November as home prices continued a downward slide for the fourth consecutive month. The median home price for an existing home in the United States dipped to $218,000, down 3.1 percent comparing to the same month one year ago.