It was not immediately clear how striking CNHI workers in Iowa would vote. A Burlington union representative could not be reached immediately for comment. CNHI declined to comment. The company raised its initial offer of an 18.5% wage hike over three years for skilled non-commercial workers, but fell short in other areas, including raising the cost of labor bonuses at the health insurance that will take effect after this year, Mahdi said. “When you factor in the increase in insurance versus wages, you lose money,” he added. The duration of the CNHI strike is unusual and far exceeds the two-month average in the United States, said Robert Bruno, a professor of labor and employment at the University of Illinois Urbana-Champaign. With a tightening job market, unionized workers at companies like Boeing and Deere & Co. have gone on strike in recent years. “What we’re seeing is union members rejecting contracts at a higher rate and the end result is that they’re doing much better,” he said.