US STOCKS SNAPSHOT-Futures fall after durable goods data

NEW YORK, Sept 25 (Reuters) - U.S. stock index futures turned negative on Friday on doubts about the strength of the economic recovery, after data showed new orders for long-lasting goods unexpectedly fell in August.

S&P 500 futures SPc1 fell 3.7 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 DJc1 fell 21 points and Nasdaq 100 futures NDc1 lost 6.5 points. (Editing by Padraic Cassidy)