U.S. stock index futures held losses on Tuesday after data showed home prices unexpectedly slid in December but the annual rate of decline slowed.

S&P 500 futures fell 4.1 points, Dow Jones industrial average futures lost 26 points and Nasdaq 100 futures dipped 6.75 points.

The widely followed Standard & Poor's/Case-Shiller index of home prices in 20 metropolitan areas unexpectedly declined in December, but the annual rate of decline slowed, reinforcing the housing market's rocky road to recovery.

Consumer confidence data, due at 10 a.m. EST (1500 GMT) is expected to show U.S. consumers are a little less upbeat.

(Editing by Jeffrey Benkoe)