Stock index futures cut gains Tuesday, with S&P futures turning flat as enthusiasm faded over upbeat data from Germany.

S&P 500 futures fell 0.7 points and were slightly under 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 rose 19 points, and Nasdaq 100 futures added 2.75 points.

(Editing by Padraic Cassidy)