By means of an event study of stock market reactions to the announcement of the Olympic Games host cities, we find a significant and positive announcement effect of hosting the Summer Games, with a cumulative abnormal return of about 2% within a few days. We do not find any significant results for the Winter Games. Neither do we detect a significant impact when bidders lose the competition. Our results differ from those of a similar study by Mirman and Sharma (2008), who find that the Winter Games are subject to a significantly negative announcement impact, while the Summer Games are not. Our results, however, rely on a larger sample of 15 Olympic events and are obtained by assessing the abnormal returns after the announcement against a "business–as–usual" situation (instead of testing the difference between winner group and loser group). Our findings are in line with economic intuition, since the Summer Games represent a larger event and are thus more likely to have a significant impact. We also find that among the winners, small economies tend to have greater cumulative abnormal returns than their large peers.
Dick, Christian and Qingwei Wang (2008), The Economic Impact of Olympic Games: Evidence from Stock Markets, ZEW Discussion Paper No. 08-060, Mannheim.