Biotechnology stocks are taking a beating Thursday, as a selloff in the broad market sends investors scurrying from riskier sectors. Some chart watchers see warning signs that the sector's long run of outperformance may finally be near an end. The SPDR S&P Biotech ETF dropped $13.52, or 5.3%, to put it on track to suffer the biggest one-day price drop in its 9 1/2-year history. Only five of the ETF's 103 components were trading higher. Among the shares of the largest components by market capitalization, Gilead Sciences Inc. slid 2.8%, Amgen Inc. shed 4.1%, Celgene Corp. slumped 3.3%, Biogen Inc. dropped 4.9% and Regeneron Pharmaceuticals fell 1.3%. "Biotech remains a top performer--not only for 2015, but over several years at this point," said Dan Wantrobski, technical analyst at Janney Capital Markets. "This issue on a short-term basis is the loss of momentum on the relative strength charts, where lower highs may be pointing to a topping formation ahead." The XBI is still up 30% year to date, while the S&P 500 has edged up 1.1%. Since the end of 2009, the XBI has soared more than four fold, while the S&P 500 hasn't quite doubled.
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