The 89% Pay Cut That Brought Trump-Mania to America's Heartland: Understanding the Republican candidate's anti-free trade, working-class appeal. Prior to Nafta, trade between the U.S. and Mexico was a relatively tame affair. The two sides alternated between deficits and surpluses—small figures, typically no bigger than a few billion dollars. U.S. exports quickly jumped after the accord went into effect in 1994, but the imports pouring in from Mexico climbed faster, and by 2015, the U.S. was posting a deficit of almost $60 billion.