 Complete the following phrase:  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 an informal agreement on September 30, 2018, which was formalized the following October 1. U.S. President Donald Trump proposed USMCA during the 