NEW YORK, July 21 (Reuters) - U.S. stock index futures jumped on Tuesday after machinery maker and bellwether Caterpillar Inc shares jumped more than 9 percent in early trade following strong quarterly results.
S&P 500 futures were up 4 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 rose 36 points and Nasdaq 100 futures gained 6.5 points.
