Investors have gotten used to bad news, but monthly layoffs topping 600,000 still made for a volatile day on Wall Street. Stocks soared, sank and then clawed their way back to a mixed close Friday after the Labor Department released its February jobs report. Employers cut 651,000 jobs, and the unemployment rate jumped to 8.1 percent. The government also revised its December and January job loss figures upward. According to preliminary calculations, the Dow Jones industrial average is up 32 at 6,626. The Standard & Poor's 500 index is up less than a point at 683. The Nasdaq composite index is down 5 1,293. Three stocks fell for every two that rose on the New York Stock Exchange. Volume came to 1.77 billion shares.