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....

Title IV of the 1990 Clean Air Act Amendments (CAAA) established a market for transferable sulfur dioxide (SO2) emission allowances among electric utilities. This market offers firms facing high marginal abatement costs the opportunity to purchase the right to emit SO2 from firms with lower...

As we understand it, the D.C. Circuit did not allow the EPA to consider the costs of complying with ozone and PM NAAQS. As we further understand it, this legal ruling can be overturned only by this Court. As economists, we believe that the D.C. Circuit's ruling not allowing the EPA to consider...