Looking Back at 50 Years of the Clean Air Act
综合回顾了美国《清洁空气法》自1970年以来的影响，分析了其在地理差异、排放、公共健康、合规成本和就业方面的效果，并指出总量控制与交易制度比传统命令控制更有效，但整体效益成本比较仍超出当前能力。
We synthesize and review retrospective analyses of federal air quality regulations to examine the contributions of the Clean Air Act (CAA) to the vast air quality improvements seen since 1970. Geographic heterogeneity in stringency affects emissions, public health, compliance costs, and employment. Cap-and-trade has delivered greater emission reductions at lower cost than conventional mandates, yet has fallen short of textbook ideals. Market power also influenced the CAA’s benefits and costs. New benefit categories have been identified ex post, but specific technology requirements have not yet been rigorously evaluated. Comparisons of aggregate benefits and costs of the CAA are beyond present capabilities.