Thursday was a bad day for stocks overall, with the Nasdaq Composite falling by more than half a percent and the broader S&P 500 posting more modest losses on the session. Most market participants blamed the downturn on a reversal of fortune for technology stocks, which have led stocks higher throughout much of 2017. With major benchmarks having pushed well into record territory for an exceedingly long time without a correction, some investors believe that a bigger pullback is inevitable.