U.S. markets opened lower as Moody\'s Investors Service downgraded credit ratings for six European countries, including Spain and Italy. The U.S. Commerce Department said retail sales rose 0.4 percent in January after falling flat in December. Excluding automobiles, sales rose 0.7 percent in the month of January. In midmorning trading, the Dow Jones industrial average gave up 27.10 points, 0.21 percent to 12,846.94. The Standard & Poor\'s 500 index shed 4.13 points or 0.31 percent to 1,347.64. The Nasdaq composite index dropped 8.34 points or 0.28 percent to 2,923.05. The benchmark 10-year treasury note rose 7/32 to yield 1.952 percent. The euro fell to $1.3168 from Monday\'s $1.3187. Against the yen, the dollar rose to 78.15 yen from Monday\'s 77.57 yen. In Tokyo, the Nikkei 225 index rose 0.59 percent, 52.89, to 9,052.07.