Home prices in January 2010 showed only minimal decline from a year earlier, according to the latest Standard & Poor’s (S&P)/Case-Shiller US National Home Price Index. The annual declines in the 10-city and 20-city composites show improvement from December's declines, but mixed results underscore the threat of a double dip in house prices. The 10-city index showed no change from January 2009, and the 20-city index declined only 0.7% during the same time. S&P/Case-Shiller notes in the latest report that annual rates for the two composites have not been so close to "a positive print" in three years, since January 2007. Both indices showed seasonally unadjusted declines and are back to their autumn 2003 levels: “While we continue to see improvements in the year-over-year data for all 20 cities, the rebound in housing prices seen last fall is fading," said David Blitzer, managing director and chairman of the S&P Index Committee, in a press statement. "Fewer cities experienced month-to-month gains in January than in December 2009, on both a seasonally adjusted and unadjusted basis.” Blitzer is not the only one seeing mixed results in the January report. Paul Dales, the US economist at Toronto-based Capital Economics, notes in e-mailed commentary that although house prices on the 20-city composite have yet to reverse recent increases, "it is only a matter of time before the index records a double-dip in prices, much like that already seen on the alternative [Federal Housing Finance Agency] FHFA measure." Dales pointed out the 0.4% monthly decline in the seasonally unadjusted 20-city composite index from December 2009 -- the fourth fall in as many months. But a "normal softness" in the market meant seasonally adjusted prices rose 0.3% in the same time -- the eighth increase in as many months, according to Dales. "This run-up in prices primarily reflects the increase in sales generated by the [first-time homebuyer] tax credit towards the end of last year, which reduced the excess supply," he said. "The real test for the market will therefore come when the tax credit expires at the end of June. At that point, we think that demand will fall back and foreclosures will continue to boost supply." Dales added: "Such a toxic combination will push prices lower again. The FHFA index, which fell in the two months to January, suggests these trends may have already begun to weigh on prices even before the tax credit has expired." Capital Economics projects prices on the Case-Shiller measure to fall back by at least 5%, undermining the "still fragile household sector" as well as the strength and sustainability of the overall economic recovery seen so far, Dales said. As of January 2010, S&P/Case-Shiller said average home prices are now at similar levels seen in the autumn of 2003. The 10-city composite fell 33.5% and the 20-city composite fell 32.6% from the peak in June and July 2006 to the April 2009 trough. The peak-to-date differences through January 2010 are -30.2% and -29.6% respectively. Write to Diana Golobay. Disclosure: the author holds no relevant investment positions.