S&P 500 index futures moved higher on Tuesday after a report showed U.S. home prices rose in August for the fourth-straight month, surpassing forecasts.

The Standard & Poor's/Case-Shiller composite index of home prices in 20 metropolitan areas rose 1.2 percent in August from July, above the 0.7 percent estimate in a Reuters poll.

S&P 500 futures rose 0.80 of a point and were above fair value, a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract. Dow Jones industrial average futures gained 9 points, while Nasdaq futures were off 2.75 points.

(Reporting by Chuck Mikolajczak; Editing by Padraic Cassidy)

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