CHICAGO (CBS) — Home prices in the Chicago area rose 1.9 percent in July from June—the third straight monthly increase, but prices dropped 6.6 percent from a year ago, according to the latest Standard & Poor’s/Case-Shiller Home Price index.

Nationally, the 10-and 20-city composites rose 0.9 percent from June, the fourth consecutive month-over-month rise in prices. But year-over year, the 10-city composite fell 3.7 percent, and the 20-city composite dropped 4.1 percent.

Seventeen of 20 metropolitan areas showed price increases month-over-month. Denver was unchanged, while Phoenix dipped 0.1 percent and Las Vegas slid 0.2 percent.

The Detroit and Washington metropolitan areas were the only areas to show year-over-year gains. In Detroit, prices rose 1.2 percent and in Washington, they rose 0.3 percent.

David Blitzer, chairman of the Index Committee at S&P Indices, noted July data reflects strong seasonal demand for houses, which is typical.

“While we have now seen four consecutive months of generally increasing prices, we do know that we are still far from a sustained recovery,” he said in a statement. “Continued increases in home prices through the end of the year and better annual results must materialize before we can confirm a housing market recovery.”

(Source: Sun-Times Media Wire © Chicago Sun-Times 2010. All Rights Reserved. This material may not be published, broadcast, rewritten, or redistributed.)