Antitrust deregulation and the U.S. listing gap

Following recent empirical evidence that industry concentration in the U.S. in recent decades is substantially explained by the weakened enforcement of antitrust laws, we examine the effects of lax antitrust enforcement on the U.S. listing gap. We construct a counterfactual scenario that simulates listing counts as if antitrust deregulation had not occurred. We find that the magnitude of the listing gap from 2002 on is considerably attenuated. We estimate that antitrust deregulation explains an average of 27 % of the annual missing listings from 2003 to 2013, or 1,265 missing listing firms per year.