U.S. stock index futures fell on Thursday after data showing an unexpected increase in new claims for jobless benefits underscored weakness in the labor market.

S&P 500 futures slipped 2.7 points and were 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 lost 20 points, and Nasdaq 100 futures shed 3.25 points.

(Reporting by Edward Krudy; editing by Jeffrey Benkoe)