U.S. stock index futures trimmed losses on Wednesday after a December gauge of manufacturing in New York State rose more than expected.

S&P 500 futures were down 4.3 points and below 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 fell 17 points, while Nasdaq 100 futures dipped 2.75 points.

(Reporting by Edward Krudy; Editing by Padraic Cassidy)