US STOCKS-Futures flat, few incentives to buy; S&P 500 off record
* Biotech stocks edge up, continuing recent rally
* Digital Ally gains before bell, has tripled this month
* Futures up: Dow 22 pts, S&P 2.5 pts, Nasdaq 6 pts
By Ryan Vlastelica
NEW YORK, Aug 26 (Reuters) - U.S. stock index futures were little changed on Tuesday, with investors finding few reasons to buy after a rally in the previous session that took the S&P 500 above 2,000 for the first time.
* The S&P failed to hold that level on Monday, though the benchmark index ended at a new closing high. Equities have rallied lately, with both the Dow and S&P advancing in seven of the last 10 sessions, while the Nasdaq has climbed in eight of the last 10 trading days.
* That momentum is still considered intact, and the S&P's price-to-earnings ratio is within historical norms, leading many analysts to believe the market is not overvalued. Nonetheless, further gains may be a challenge without positive catalysts and amid potential headwinds such as a reduction in Federal Reserve stimulus and a simmering conflict between Ukraine and Russia.
* Much of the market's recent gains have come on low volume, suggesting many traders may be reluctant to jump in at current levels.
* S&P 500 e-mini futures rose 2.5 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 e-mini futures added 22 points and Nasdaq 100 e-mini futures added 6 points. Continuación...