A digressive tax such as a variable rate sales tax or a tax on price gives firms an incentive for expanding output. Thus, unlike unit and ad valorem taxes which amplify the harm from monopoly, a digressive tax lessens the harm. We analyse a tax on price with respect to efficiency and practical...

The efficiency of the Pigouvian tax suggests that price-based regulation is the proper benchmark for efficient regulation. However, results due to Carlton and Loury (1980, 1986) question this; when harm depends on scale effects a pure Pigou tax is inefficient regulation in the long run. In this...