U.S. stock index futures trimmed gains on Friday after January U.S. employment rose far less than expected.

S&P 500 futures added 3 points and were slightly 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 added 10 points, and Nasdaq 100 futures gained 1.5 points.

(Reporting by Angela Moon; Editing by Padraic Cassidy)