Ex post evaluation of competition policy enforcement : what can we learn from the literature and from the experience of competition authorities?

A lot can be learnt from existing work on the micro and macroeconomic impacts of competition policy. Overall, this review of the literature confirms that competition policy contributes to the good functioning of markets and improves consumer welfare. The empirical research on the microeconomic impact of competition policy shows that the deterrent effects of merger control and antitrust enforcement largely outweigh the costs of maintaining an effective competition regime, and that the stronger enforcement of cartel policies has contributed to a decline in overcharges. Work on the macroeconomic impact shows that competition policy and competition have a positive effect on growth, in particular via their effects on mark-ups, business dynamism, innovation and productivity. This effect is particularly important in countries and sectors where there is greater scope for reducing mark-ups. For example, aligning mark-ups in the euro area services sector to those in the United States could increase real GDP in the long term by 4.4%.