Stock indexes slip again, but Herbalife jumps

U.S. stock indexes edged lower in early trading Monday, following back-to-back losses for the Standard & Poor's 500 index over the last two weeks. KEEPING SCORE: The S&P 500 was down 2 points, or 0.1%, to 2,423, as of 10 a.m. EDT. The Dow Jones industrial average fell 42 points, or 0.2%, to 21,632....