US stock markets opened flat Wednesday after research firm Markit Economics said U.S. manufacturing reached a five-month peak in November. The Purchasing Manager\'s Index climbed to 52.4 in the month, on a scale in which numbers above 50 indicate businesses are expanding. In a weekly report released a day early, the Labor Department said 41,000 fewer first-time unemployment claims were filed in the week ending Saturday, with initial claims falling to 410,000, the numbers still skewed in the wake of Hurricane Sandy. In midmorning trading Wednesday, the Dow Jones industrial average added 18.78 points or 0.15 percent to 12,806.69. The tech-heavy Nasdaq composite index shed 2.34 points or 0.08 percent to 2,914.35. The S&P 500 lost 0.50 points or 0.04 percent to 1,387.31. The benchmark 10-year treasury fell 5/32 to yield 1.687 percent. The euro fell to $1.2815 from Tuesday\'s $1.2818. Against the yen, the dollar rose to 82.34 yen from 81.69 yen. In Tokyo, the Nikkei 225 index added 0.87 percent, 79.88 points, to 9,222.52.