After three straight red sessions S&P 500 index retreated and traded slightly higher on Friday supported by financial and energy shares. US benchmark added 0.31% or 4.33 points and finished at 1,397.11. Discover Financial and Nabors Industrials each climbed 4% posting the biggest gains for the index. On the downside Micron Technology shed 3.8% after company revealed larger than expected loss. Nike fell 3% despite reporting better than expected EPS for the third quarter.