Stock index futures added to gains on Wednesday after data showed new U.S. orders for long-lasting manufactured goods unexpectedly rebounded in February.

We've seen a variety of different data points that suggest that though we're not completely done with the deterioration in the overall economy, we're clearly seeing signs of a thaw, said Peter Kenny, managing director at Knight Equity Markets in Jersey City, New Jersey.

S&P 500 futures rose 2.10 points 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 climbed 31 points, while Nasdaq 100 futures rose 5.75 points.

(Reporting by Leah Schnurr and Ryan Vlastelica; Editing by James Dalgleish)