A Sector Leaders list depleted by a correcting stock market is showing signs of wear. It’s IBD’s toughest screen, and when the market corrects, fewer stocks can cut the mustard. That’s why the list has fallen to just nine names. It had been as many as 16 stocks less than a week ago. Jazz Pharmaceuticals (JAZZ), a long-time resident of Sector Leaders and other IBD screens of top-performing stocks, plunged deeper below its 50-day line Friday.