Three problems in applying contestability to regulated markets

The theory of contestable markets emphasizes that the ease of entry rather than the number of existing firms forces incumbents to set prices at optimal levels. The policy implications of this work contrast sharply with past U.S. regulatory and antitrust policies, legitimizing increased industry concentration and decreased regulation. This paper explores three factors that influence the desirability of regulation or antitrust policy despite the apparent existence of a contestable market time lags, technological change, and cyclical macroeconomic fluctuations. Time lags enable incumbents to earnsupra-normal profits and take last-minute action to forestall entry. New technologies can create sunk costs that reduce the contestability of a market. Recessions can depress capital markets, raising the cost of exit, while expansion creates opportunities for entry without threatening monopolistic prices. These shortcomings limi the ability of contestability theory to provide guidelines for the regulation of actual industries.