The S&P/Case-Shiller home-price index dropped 10.7 percent from January 2007, after a 9 percent year-on-year decrease through December 2007. The gauge has fallen for 13 consecutive months.
Here’s an inflation-adjusted chart of the CSI:

http://calculatedrisk.blogspot.com/2008/03/real-case-shiller-house-price-index.html