Meanwhile, another study estimates that achieving – or even exceeding – that the Paris targets could be very beneficial on a global scale by investing in infrastructure in clean energy and energy efficiency, to the amount of about $19 trillion. The Paris Agreement was inaugurated at signing on 22 April 2016 (Earth Day) at a ceremony in New York. [59] Following the ratification of the agreement by several European Union states in October 2016, there have been enough countries that have ratified the agreement to produce enough greenhouse gases worldwide for it to enter into force. [60] The agreement entered into force on November 4, 2016. [2] Trump made his claim about the impact of the agreement on global warming in a speech on June 1 in which he announced that the United States would „withdraw“ from the international agreement.