Single-family home prices remained in freefall in July, according to the S&P/Case-Shiller Home Price Indices released by Standard& Poor's Tuesday morning.

The Case-Shiller 10-City Composite Index for July sank to 178.46, 17.5% below its level in July of 2007 and its 10th consecutive month of record declines. The index is based on a score of 100 in January, 2000. The 20-City Composite Index fell to 166.23, 16.3% below last year.

Home prices have now fallen 21.1% in the 10-City Index and 19.5% in the 20-City Index since the peak of the market, which Case-Shiller estimates was June/July 2006.

The rate of decline, which began slowing in May, ticked up slightly between June and July, with the 10-City Composite rate falling 1.1% month-to-month and the 20-City dropping 0.9% month-to-month. In comparison, the month-to-month drops from May to June were 0.6% and 0.5% respectively.

Still, from May through July, home prices fell 2.2%, compared to a drop of 6% from February through April and 6.5% from November through January.

"There are signs of a slowdown in the rate of decline across the metro areas, but no evidence of a bottom," said David M. Blitzer, chairman of the Index Committee at Standard & Poor's. "Little positive news can be found when cities like Las Vegas and Phoenix report annual declines as large as minus 29.9% and minus 29.3%, respectively, and all 20 cities are still in negative territory on a year-over-year basis."

"The Sunbelt continues to be the story," Blitzer continued, "with the seven cities that basically represent that area reporting annual declines roughly between 20 and 30%. While some cities did show some marginal improvement over last month's data, there is still very little evidence of any particular region experiencing an absolute turnaround."

Las Vegas remains the weakest market, reporting an annual decline of 29.9%, followed by Phoenix and Miami at -29.3% and -28.2%, respectively. Atlanta, Dallas, Minneapolis and Tampa showed improvements in their annual and monthly returns, but all four are still too close to their recent lows to determine if the markets have stabilized, S&P said. While their annual returns are negative, Atlanta, Boston, Dallas, Denver and Minneapolis all reported positive returns for the three months or more.

Market by market, Atlanta was up 0.4% from June to July but remains down 8.2% year-over-year; Boston +0.2% and -5.4%, respectively; Charlotte -0.2% and -1.8%; Chicago -0.4% and -10.0%; Cleveland -0.3% and -7.8%; Dallas +0.6% and -2.5%; Denver +0.8% and -4.7%; Detroit +0.6% and -16.7%; Las Vegas -2.8% and -29.9%; Los Angeles -1.6% and -26.2%; Miami -1.6% and -28.2%; Minneapolis +1.3% and -13.1%; New York -0.8% and -7.4%; Phoenix -2.7% and -29.3%; Portland -0.5% and -6.6%; San Diego -1.8% and -25.0%; San Francisco -1.8% and -24.8%; Seattle -1.0% and -8.2%; Tampa 0.0% and -19.4%; and Washington -1.1% and -15.8%.