U.S. home prices continued to fall at a record pace through the first half of 2008, according to a major indicator reported Tuesday.

U.S. home prices continued to fall at a record pace through the first half of 2008, according to a major indicator reported Tuesday.

The Standard & Poor's/Case-Shiller U.S. national home price index fell 15.4 percent in the second quarter compared with the same period a year earlier. The decline was the largest in 20 years for the index, which covers the entire United States.

Las Vegas posted the sharpest decline among cities, with June prices down 28.6 percent from a year ago. Miami, with a 28.3 percent decline, was next, followed by Phoenix, which saw prices fall 27.9 percent from the previous June. Los Angeles home prices were down 25.3 percent in the year-over-year period, putting it in fourth place.

Every city in the index posted an annual price decline, but in Charlotte, N.C., that drop was 1 percent.

In addition to the quarterly national index, Standard & Poor's released its monthly index of 20 major metropolitan areas, which also posted record declines. June home prices were down 15.9 percent from a year ago in the 20-city index.

Standard & Poor's analysts noted that the 15.9 percent June decline was only a moderate dip from its May decline of 15.8 percent from May 2007.

"It is possible we are seeing some regions struggling to come back, which has resulted in some moderation in price declines at the national level," said David M. Blitzer, chairman of the index committee for Standard & Poor's.

Blitzer cited as examples Charlotte and Dallas, which have seen month-to-month price increases in the past four months. Compared with the same month a year ago, however, both cities posted price declines.

Those cities did not experience the same large price gains during the housing boom as the cities now showing the worst declines.

The Case-Shiller index compares the latest sales of detached houses with previous sales. It accounts for factors such as remodeling that might affect a house's sale price over time. From those data, an index score is created to show price changes.

The 20-city index for June was down 18.8 percent from its peak in July 2006.

More bleak housing news came Tuesday from the U.S. Census Bureau and the Department of Housing and Urban Development. The agencies reported that July new home sales were down 35.3 percent from the same month last year. However, the number of new homes sold in July was up 2.4 percent from June.