At the time that NAFTA
went into effect, about 40% of U.S. imports from Mexico entered duty-free and the remainder
faced duties of up to 35%, with a trade-weighted average rate of about 7%. Mexico’s tradeweighted
tariff on U.S. agricultural products averaged about 11%. Also affecting U.S.-Mexico
trade were both countries’ phytosanitary rules, Mexican import licensing requirements, and U.S.
marketing orders