US STOCKS-Wall St dips as third-quarter earnings season kicks off
* IMF cuts global growth view for second time
* DuPont jumps after CEO resigns
* Pfizer, Merck drag down S&P health index
* Yum! shares fall after results
* Dow up 0.08 pct, S&P down 0.36 pct, Nasdaq down 0.69 pct (Updates to close)
By Noel Randewich
Oct 6 (Reuters) - U.S. stocks fell on Tuesday, ending a five-day winning streak, as investors focused on upcoming quarterly reports that are expected to reflect a dip in corporate earnings.
A surge in DuPont's stock helped keep the Dow Jones industrial average in positive territory but the S&P 500 and Nasdaq lost ground, with a sharp drop in biotech stocks.
The S&P health index lost 2.33 percent, the worst performer among the ten major S&P sectors. The sector has been under intense scrutiny over high drug prices. Continuación...