US STOCKS-Futures dip before payrolls; on track for weekly fall
* Payrolls data on tap
* Gap falls in premarket after August sales
* Prana Biotech jumps on orphan drug designation
* Futures off: Dow 53 pts, S&P 6.75 pts, Nasdaq 6 pts
By Chuck Mikolajczak
NEW YORK, Sept 5 (Reuters) - U.S. stock index futures fell on Friday, putting the S&P 500 on track for its first lower week out of five, as investors awaited the monthly employment report.
* The benchmark index has fallen for three straight sessions since closing at a record high of 2,003.37 a week ago. Both the Dow Industrials and S&P 500 managed to touch fresh intraday highs on Thursday, before weakness in energy shares caused major indexes to retreat.
* Investors were looking ahead to the August jobs report, due at 8:30 a.m. EDT (1230 GMT), to assess the economy's strength and possible timing of an interest rate hike by the Federal Reserve. Estimates call for nonfarm payrolls to rise to 225,000 and the unemployment rate to fall to 6.1 percent. A reading above 200,000 would mark the seventh straight month at such a pace, a streak not seen since 1997.
* S&P 500 e-mini futures were down 6.75 points and fair value - a formula that evaluates pricing by taking into account interest rates, dividends and time to expiration on the contract - indicated a lower open. Dow Jones industrial average e-mini futures fell 53 points and Nasdaq 100 e-mini futures lost 6 points. Continuación...