Data through August 2010, released today by Standard & Poor’s for its S&P/Case-Shiller1 Home Price Indices, the leading measure of U.S. home prices, show a deceleration in the annual growth rates in 17 of the 20 MSAs and the 10- and 20-City Composites in August compared to what was reported for July 2010. The 10-City Composite was up 2.6% and the 20-City Composite was up 1.7% from their levels in August 2009. Home prices decreased in 15 of the 20 MSAs and both Composites in August from their July levels.

The 10-City and 20-City Composite Home Price Indices showed increases of 2.6% and 1.7%, respectively, in August 2010 compared to the same month in 2009. In August, 12 of the 20 MSAs posted negative annual growth rates. This is two more than what was reported in July, as Detroit and Miami posted negative annual rates in August. While still negative, three of the 20 MSAs saw improvement in year-over-year growth rates in August as compared to July. They are Charlotte, Cleveland and Las Vegas with annual growth rates of -3.4%, -0.4% and -4.5%, respectively. Annual growth rates slowed down in the three California cities, with Los Angeles, San Diego and San Francisco posting annual gains of +5.4%, +6.9% and +7.8%, respectively – a significant drop from the +7.5%, +9.3% and +11.2% reported for July.

A disappointing report. Home prices broadly declined in August. Seventeen of the 20 cities and both Composites saw a weakening in year-over-year figures, as compared to July, indicating that the housing market continues to bounce along the recent lows. Over the last four months both the 10- and 20-City Composites show slowing growth, after sustaining consistent gains since their April 2009 troughs.

The month-over-month growth rates tell the same story. Fifteen of the 20 MSAs and the two Composites saw a decline in the month of August as compared to July levels. The 10- and 20-City Composites fell 0.1% and 0.2%, respectively. Indeed, the housing market appears to have stabilized at new lows. At this time, it does not seem that any of the markets are hanging on to the temporary momentum caused by the homebuyers’ tax credits.

As of August 2010, average home prices across the United States are back to the levels where they were in late 2003 and early 2004. Measured from June/July 2006 through August 2010, the peak-to-current declines for the 10-City Composite and 20-City Composite are -28.4% and -28.1%, respectively. The improvements from their April 2009 trough are +7.8% and +6.7%, respectively.

With August data, we find that 15 of the 20 MSAs and both Composites saw prices fall from their July values. Chicago, Detroit, Las Vegas, New York and Washington DC were the only five cities that recorded marginal improvements in home prices over July. The 10- and 20-City Composites were down 0.1% and 0.2%, respectively, in August versus July.

Chicago, Detroit, New York and Washington DC have all posted at least four consecutive months of positive increases in home prices; but none of the MSAs had monthly increases of greater than 1% in August. San Diego, which had posted 15 consecutive months of positive monthly change, recorded a 0.6% drop in average home prices in August. The same is true of Atlanta, Boston, Los Angeles, Miami, Minneapolis, San Francisco, Seattle and the two Composites – they all broke their trend of several consecutive months of positive monthly gains with August’s report.