Trump has made many false or misleading statements during his campaign and presidency. The statements have been documented by fact-checkers, with political scientists and historians widely describing the phenomenon as unprecedented in modern American politics. Trump's approval rating has been stable, hovering at high-30 to mid-40 percent throughout his presidency. Trump rolled back numerous environmental protections, as well as reduced enforcement of existing regulations. He ended the Clean Power Plan, withdrew from the Paris Agreement on climate change mitigation, and urged for subsidies to increase fossil fuel production, calling man-made climate change a hoax. Trump failed in his efforts to repeal the Affordable Care Act (ACA), but took numerous actions that hindered the functioning of the ACA, as well as sought to have the courts rule the entirety of the ACA unconstitutional.