We synthesize and review retrospective analyses of federal air quality regulations to examine the contributions of the Clean Air Act to the vast air quality improvements seen since 1970. Geographic heterogeneity in stringency affects emissions, public health, compliance costs, and employment....

This paper considers the treatment of co-benefits in benefit-cost analysis of federal air quality regulations. Using a comprehensive data set on all major Clean Air Act rules issued by the Environmental Protection Agency over the period 1997-2019, we show that (1) co-benefits make up a...