Stocks were near their session lows in late-afternoon trade Monday. The Nasdaq outperformed early, but slipped into the red. Hurt by weakness in oil stocks, the S&P 500 fell 0.5%. It’s now back below the psychological 2000 mark. The Dow Jones industrial average fell 0.3%. Meanwhile, the Nasdaq turned an early 0.4% gain into a 0.1% loss. Turnover was mixed in the stock market today.