The S&P/Case-Shiller Home Price Indexes' 10-City Composite and 20-City Composite reached new record annual declines of 17.5% and 16.3%, respectively, through the end of July, the most recent period tracked by S&P.

The 10-City Composite Index declined at a record level for the 10^th consecutive month. Taken together, these declines far surpass the record decline of 6.3% in a similar market trough between 1990-1992.

The news is not all bad, however. Overall declines have actually slowed in home prices in the most recent three-month period.

Cumulative home prices fell 2.2% for the three months ended July, whereas for the previous two consecutive three-month periods, the cumulative home price fall was more than triple that level, between 6-6.5%.

While the slowdown in home price declines is notable across metro areas, it does not necessarily mean a bottom has been reached in the market, and some metro markets continue to post outsized declines, S&P indicated.

All 20 major metro markets are still in negative territory year-over-year, and Las Vegas (-29.9%) and Phoenix (-29.3) had annual declines nearing 30%. The Sun Belt as a whole continued to be in the dark, with its seven major metro markets all posting declines of at least 20%. Don't make a bet on Vegas' home market, either: It continues to be the big loser at the table in terms of home price declines, followed by Phoenix and Miami (-28.2%).

Other major metro markets seem on the verge of a rebound, but S&P remains cautious on outlook.

Atlanta, Dallas, Minneapolis and Tampa all showed improvements in home pricing with the new monthly and annual data, but S&P indicated the markets remained too near recent lows to be demonstrating clear evidence of a turning tide. Atlanta, Boston, Dallas, Denver and Minneapolis all had positive returns for the past three months through the end of July. The smallest dips for the annual period through July were Charlotte (-1.8); Dallas (-2.5%); and Denver (-4.7%)

In the same 2007 annual period, the S&P/Case-Shiller Home Price Indexes fell 4.5% and 3.9%, respectively. The only five metropolitan areas last July to show positive one-year returns were Atlanta, Charlotte, Dallas, Portland and Seattle (see story here).