Stocks greeted 2016 by sliding more than 1% Monday, hurt by a rout in Chinese stocks overnight and increased tensions in the Middle East. The Nasdaq slumped 2.1%, the Dow Jones industrial average lost 1.6% and the S&P 500 fell 1.5%. All three indexes were off more than 2% most of the day. Volume jumped 69% on the NYSE and 61% on the Nasdaq compared to Thursday’s pre-holiday levels, according to preliminary data.