Reports, Case Studies & Assessments Benefits and Costs of the Clean Air Act 1990-2020, the Second Prospective Study Published 2011 Share SHARE Facebook share Twitter LinkedIn Copy URL Email Download Download fullreport_rev_a.pdf en Added on: 20 May, 2025 Breadcrumb Home Resource Library Benefits and Costs of The Clean Air Act 1990-2020, The Second Prospective Study In March 2011, EPA issued the Second Prospective Report which looked at the results of the Clean Air Act from 1990 to 2020. According to this study, the central benefits estimate exceeds costs by a factor of more than 30 to one. The report was updated in April 2011.