The Associated General Contractors of America, the nation's largest construction trade association, called on Secretary of Commerce Donald Evans to temporarily lift tariffs imposed upon Mexican cement products. The request came in light of domestic price increases and reported shortages of cement in many parts of the country. According to AGC CEO Stephen E. Sandherr, cement demand has increased more than 8 percent in the last six months as the U.S. economy has improved. Cement prices are expected to increase by as much as 15-20 percent over the next few months as domestic mills are operating at or near capacity.