The same March 2017 executive order that directed the EPA to reconsider existing greenhouse gas regulations also jettisoned the federal social cost of carbon (SCC), a set of standardized values developed during the Obama administration to monetize the climate change benefits of proposed regulations. Because agencies must justify major regulations through a largely monetized cost-benefit analysis (CBA), the resulting calculations play a critical role in determining both the stringency and viability of regulatory standards. President Trump’s order withdrew all documents relating to the federal SCC, including background technical documents detailing the economic costs of global warming. Although President Trump’s order did not prohibit agencies from attempting to calculate climate benefits, it required any subsequent analyses to follow strictly a 2003 Office of Management and Budget (OMB) guidance document, Circular A-4, that directs agencies to discount steeply the value of preventing future harms and to focus on impacts within the United States. Indeed, President Trump’s EPA applied these limitations to assess the costs and benefits of repealing the Obama administration’s Clean Power Plan and to support replacing it with much less effective power plant efficiency improvement guidelines.