The latest edition of the reliable home price index is depressing. Standard & Poor’s/Case-Shiller 10-city composite index for August 2008 declined by a record amount, down 17.7% from a year earlier.

20 Years of S&P Case-Shiller Home Index

20 Years of S&P Case-Shiller Home Index

Nevada lead the way down, again:

Cities with the largest annual declines in home prices are Phoenix and Las Vegas, where prices have declined more than 30% over the past year. Other cities with declines higher than 25% are Miami, San Francisco, Los Angeles and San Diego.

But perhaps a national trend can be noticed already. After twelve-fifteen years of steady rise, prices went up exponentially until the cap, and started to drop also exponentially. If this bell figure materializes, prices should get back to the “normal” range by late 2009:

a forecast?

S&P Case-Shiller Home Index: a forecast?

Case-Shiller data is available online.

UPDATE: Since this post Case-Shiller has published data for two more months, September and October. The Bell trend remains, with Sep-08 and Oct-08 matching the values of Apr-04 and Mar-04. If the trend confirms, 2009 and 2010 will see more price declines, albeit decelerating.

Of course, that is based on the Composite 10-City Index, which ends up masking out local trends. For Portland-Vancouver, Chicago and Charlotte, the bell shape is almost complete.