Stocks waver as chipmakers jump, drug companies dip

Stocks finished mostly higher Thursday as another day of mixed trading showed the market’s recent rally losing some strength. Chipmakers rose, while drugmakers fell.

Chipmakers Xilinx and Lam Research soared and many of their peers also climbed as investors, many of whom have been pessi- mistic about demand for computer chips recently, saw signs of life in the business. The Philadelphia Semiconductor Index rose to its highest level since early December. Airlines also rose after several strong quarterly reports.

About two-thirds of the stocks on the New York Stock Exchange closed with gains, but major stock indexes didn’t move much. Drugmakers including Merck and Pfizer took sharp losses, and spice maker McCormick had its biggest drop in 13 years. Other household products companies also sank.

The S&P 500 index rose 3.63 points, or 0.1 percent, to 2,642.33. The benchmark U.S. index is up 12.4 percent over the last month, but it’s slipped 1.1 percent this week after big gains in each of the past four weeks. The Dow Jones Industrial Average dipped

22.38 points, or 0.1 percent, to 24,553.24.

Thanks to the big gains for technology companies, the Nasdaq composite added 47.69 points, or 0.7 percent, to 7,073.46. The Russell 2000 of smallcompany stocks gained

10.15 points, or 0.7 percent, to 1,464.41.