Note: This figure does not contain low-value, low-value export shipments. The statistics come from the U.S. Harmonized Tariff Plan (HTS) at the four-digit level. The HTS consists of a hierarchical structure describing all goods marketed for customs, quota and statistical purposes. This structure is based on the harmonised international system of description and codification of raw materials (SH), managed by the World Customs Organization in Brussels. The overall effect of the agricultural agreement between Mexico and the United States is controversial. Mexico has not invested in the infrastructure needed for competition, such as efficient railways and highways. This has led to more difficult living conditions for the country`s poor. Mexico`s agricultural exports increased by 9.4% per year between 1994 and 2001, while imports increased by only 6.9% per year over the same period.  Nafta has nevertheless been a recurring objective in the broader debate on free trade. President Donald J. Trump says it undermines U.S.
jobs and manufacturing, and in December 2019, his administration finalized an updated version of the pact with Canada and Mexico, now known as the U.S.-Mexico-Canada Agreement (USMCA). The USMCA received broad support from all parties on Capitol Hill and came into force on July 1, 2020. In October 2017, in The Globe and Mail in Toronto, an op-ed questioned the U.S. willingness to renegotiate the agreement or whether it planned to do so, no matter what, and noted that the newly appointed U.S. Ambassador, Kelly Knight Craft, is married to the owner of Alliance Resource Partners, a major U.S. coal company. Canada is implementing a carbon plan, and it is also about selling bomber jets. « Americans used so many poison pills in last week`s conversations in Washington that they should have been charged with murder, » columnist John Ibbitson wrote.  The trade statistics in this paragraph are based on trade data from the Ministry of Commerce. Shortly after the start of his presidency, President Clinton addressed labour and environmental issues by speaking with his Canadian and Mexican counterparts about formal joint agreements. NAFTA laws contained provisions for ancillary agreements authorizing U.S.
participation in NAFTA Labour and Environment Commissions and funds for those activities.