The Agreement between the United States of America, the United Mexican States, and Canada (USMCA) is a free trade agreement between Canada, Mexico, and the United States. It replaced the North American Free Trade Agreement (NAFTA) implemented in 1994, and is sometimes characterized as "NAFTA 2.0", or "New NAFTA", since it largely maintains or updates the provisions of its predecessor. USMCA created one of the world's largest free trade zones, spanning roughly 500 million people and totaling over $26 trillion in GDP (PPP). USMCA resulted from renegotiations between the NAFTA member states beginning in 2017; characterized as "tumultuous", these centered primarily on "auto exports, steel and aluminum tariffs, and the dairy, egg, and poultry markets". All sides came to a formal agreement on October 1, 2018, and U.S. President Donald Trump proposed USMCA during the G20 Summit the following month, where it was signed by himself, Mexican President Enrique Peña Nieto, and Canadian Prime Minister Justin Trudeau. A revised version reflecting additional consultations was signed on December 10, 2019 and ratified by all three countries, with Canada being the last to ratify on March 13, 2020. Following notification by all three governments that the provisions were ready for domestic implementation, the agreement came into effect on July 1, 2020. USMCA is primarily a modernization of the 25-year-old NAFTA, namely with respect to intellectual property and digital trade, and borrows language from the Comprehensive and Progressive Agreement for Trans-Pacific Partnership (CPTPP), of which Canada and Mexico are signatories. Key changes from its predecessor include increased environmental and working regulations; greater incentives for automobile production in the U.S. (with quotas for Canadian and Mexican automotive production); more access to Canada's dairy market; and an increased duty-free limit for Canadians who buy U.S. goods online. Background and nomenclature The United States–Mexico–Canada Agreement is based substantially on the North American Free Trade Agreement (NAFTA), which came into effect on January 1, 1994. The present agreement was the result of more than a year of negotiations including possible tariffs by the United States against Canada in addition to the possibility of separate bilateral deals instead. During the 2016 U.S. presidential election, Donald Trump's campaign included the promise to renegotiate NAFTA, or cancel it if re-negotiations were to fail. Upon election, Trump proceeded to make a number of changes affecting trade relations with other countries. Withdrawing from the Paris Agreement, ceasing to be part of negotiations