Knowledge check here is a chart of the Nasdaq Composite , the world's main technology index. It peaked in the dotcom bubble on March 10, 2000 The P/E ratio later peaked above 500. In hindsight , this is widely agreed to have been a bubble. In March 2015, the index value for the first time since then surpassed the peak. why might some investors at that point have argued " this time it's different"?