The magnificent 7 uphold a lot of weight in the QQQ, S&P Index and a responsible for a large percentage of their gains. In fact they hold so much weight of the QQQ that if you held the Q's rather then the MAG 7 you would have earnt 1/3. By holding the SPX you would of earnt 1/5 of the amount. Since mid 2012. So a underperformance of these stocks would largely drag down both index's Other divergence to be displayed in the index.