Shareholder wealth effects of legislative events: The case of airline deregulation

This paper presents empirical evidence about the impact on shareholder wealth of legislative events leading to the enactment of the Airline Deregulation Act of 1978. In contrast to prior regulatory event studies, this paper examines not only the final legislative enactment but also the Congressional hearings that preceded it. No significant effect on shareholder wealth is indicated when averaged across all airline firms and all legislative events. Impact of deregulation, however, was expected to be different for trunk airlines than for local airlines. Moreover, market expectations likely changed with the change in the political climate during the course of deregulation deliberations, from an industry financial health emphasis under a Republican (Ford) administration to a consumer welfare emphasis under a Democratic (Carter) administration. We find that trunk airlines experienced significant positive abnormal returns during the Ford administration, but negative abnormal returns during the Carter administration. In contrast, local airlines exhibited significant negative abnormal returns during both the Ford and Carter eras. Systematic risk of both trunk and local airlines also increased with the change in the political climate.