NEW YORK, Feb 28 (Reuters) - The S&P 500 index futures briefly turned negative on Thursday following mixed data reports that showed that the U.S. economy barely grew in the fourth quarter, though the latest weekly jobless claims data pointed to an improving labor market. S&P 500 futures were flat and in line with 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 added 3 points and Nasdaq 100 futures rose 1.5 points.

* S&P 500 has gained 1.9 percent over past two sessions * Fourth-quarter GDP may be revised to show growth * J.C. Penney, Groupon both sink on weak revenue * Futures up: Dow 16 pts, S&P 2.7 pts, Nasdaq 4.5 pts By Ryan Vlastelica NEW YORK, Feb 28 (Reuters) - U.S. stock index futures edged modestly higher on Thursday as investors were reluctant to make big bets following a sharp two-day rally and ahead of a rash of data.

* U.S. Chairman Bernanke to speak at 10:00 a.m. ET * Italy bonds, European stocks up after Italy bond auction * Futures: S&P up 2.5 pts, Dow off 1 pt, Nasdaq off 0.25 pt By Angela Moon NEW YORK, Feb 27 (Reuters) - U.S. stock index futures were little changed on Wednesday as investors awaited a second round of testimony in Congress by Federal Reserve Chairman Ben Bernanke for signs of whether the Fed will continue its economic stimulus program.

* HP climbs after earnings, outlook * German business morale jumps, fastest pace in over 2 years * S&P on pace for first weekly loss of year * Futures up: Dow 73 pts, S&P 8.2 pts, Nasdaq 14.75 pts By Chuck Mikolajczak NEW YORK, Feb 22 (Reuters) - U.S. stock index futures rose on Friday, indicating the S&P 500 would rebound after two days of losses, boosted by better-than-expected earnings from Hewlett-Packard and positive economic data from Europe.