 Shares of United States Steel Corp. X, 4.75 rallied 4.5 toward a two-month high in afternoon trading Tuesday, after the steel maker said it reached a tentative agreement with United Steelworkers USW labor union on a new four-year contract. The company said the contract covers 11,000 employees represented by the USW at its U.S. flat-rolled and iron ore facilities, and the applicable tubular operations. 