The Standard & Poor’s/Case-Shiller Housing Price Indices are out today, and show that the yearly price performance in the traditional 10-city index during July was the worst since 1991 — the 10-city composite for July 2007 was down 4.5 percent versus 2006 levels. Check out the longitudinal trending here: 15 of the 20 metro areas now tracked in the Case-Shiller indices are showing negative annual returns. From the press statement:

While five of the metro areas – Atlanta, Charlotte, Dallas, Portland and Seattle – are still registering positive annual returns, all five have shown deceleration in their rates of growth during the past year. Both Atlanta and Dallas are getting closer to joining 15 other metro areas in registering a year-over-year decline in home prices.

“The decline in home prices clearly continued into the summer months,” says Robert J. Shiller, Chief Economist at MacroMarkets LLC. “The year-over-year decline reported for the 10-City Composite is the lowest since July 1991. The lowest annual decline in this Index, which dates back to January 1987, was -6.3%, which was reported in April 1991. The further deceleration in prices is still apparent across the majority of regions, with 16 of the 20 metro areas showing a drop in their annual growth rate from what was reported in June.” For more information, visit http://www.standardandpoors.com.