Midday Report: Costco Sinks; Dow Chemical Boosts S&P 500

Stocks extended gains by midday Wednesday as reports of merger talks between Dow Chemical (DOW) and DuPont (DD) led a beat-up materials sector higher. Materials had a rough day on Tuesday after the latest Chinese trade data flamed fears over demand. Kinder Morgan (KMI) slid after slashing its 2016 quarterly dividend to 12.5 cents a share, a quarter of the value of its current dividend. Costco (COST) dragged on the S&P 500 after a disappointing quarter. Membership fees were the main concern, rising under 2% to mark the slowest growth in years. Oil prices rallied after crude supplies declined for the first time in 11 weeks. The EIA reported a drop of 3.6 million barrels in U.S. inventories in the past week.