The International Monetary Fund released a  report evaluating the economic impact of the recently renegotiated North American Free Trade Agreement (NAFTA).  If ratified by the legislatures of Canada, Mexico, and the United States, the reformulated agreement that President Trump is calling the USMCA (United States - Mexico - Canada Agreement) would ultimately have little overall economic impact.  The marginal benefits go to Canada and Mexico with the U.S. as the sole loser of the renegotiation, according to the study.  While certain custom provisions (e.g. increasing the  de minimis thresholds in Canada and Mexico) would help overall trade on the continent, other provisions in the deal (e.g. local content requirements for automotive imports) would hamper it.

Separately, the U.S. International Trade Commission (ITC) is conducting its own analysis of the economic impact of the deal.  That report, which is mandated by Congress, is due to be released by mid-April.  Early expectations are that the ITC will come to relatively similar conclusions.  

Both reports make it even less likely that the renegotiated agreement will ultimately be ratified.  Ratification is already facing various challenges in both the House and the Senate from both Republicans and Democrats on issues spanning from longer intellectual property right protections for biologics (a type of pharmaceutical) to steel and aluminum tariffs.  In Canada, upcoming national elections could possibly result in Prime Minister Justin Trudeau losing a legislative majority.  In Mexico, President Andrés Manuel López Obrador did not sign or take part in the renegotiation of the agreement.  While he is currently supportive of the agreement, that could change if the U.S. seeks to modify labor standards or enforcement provisions to appease the Democratic majority in the House.