NEW YORK (AP) β Stocks are heading mostly lower in midday trading as an early gain fades away.
If the market ends down Wednesday it would extend a slump into a third day.
Costco led a drop in consumer staples stocks after reporting weaker earnings than analysts were expecting.
Dow Chemical and DuPont rose sharply following reports that the two companies were talking about a combination.
Energy and materials companies moved higher along with the price of oil and other commodities.
The Standard & Poor's 500 index lost four points, or 0.2 percent, to 2,059 as of 11:45 a.m. Eastern time. The Nasdaq composite gave up 44 points, or 0.9 percent, to 5,053.
The Dow Jones industrial average got a boost from DuPont. The 30-stock average increased 12 points, or 0.1 percent, to 17,581.