Based on two-country scenarios (entrants vs. incumbents), this paper employs the synthetic control method to quantify the macroeconomic effects of the European Union (EU) enlargement, and examines whether these effects varied before, during, and after economic crises. We find that enlargement effects are very complex, and significantly varied across economic cycles and the country groups. In particular, EU enlargement induced large and positive effects on the entrants which were merely stifled in the wake of the financial crisis and the subsequent euro crisis. In the interim, the 2004 enlargement triggered an instantaneous negative shock on the incumbents which was further exacerbated by the crises. Subsequently, the entrants recovered beyond their pre-crises gains, registering approximately 14 % higher per capita incomes by 2019, with Poland emerging as a clear winner. Meanwhile, incumbents’ per capita incomes have, on average, declined by approximately 9 %. While our findings largely support the notion that the entrants are en route to catching up with their incumbent counterparts, a formal β-convergence analysis exploiting the observed and synthetic data intuitively confirms that EU integration reduces the half-life by 50 %.

中文翻译：

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使一些船只扬起的浪潮：评估欧盟东扩的宏观经济影响

本文基于两国情景（进入者与现有者），采用综合控制方法来量化欧盟（EU）东扩的宏观经济影响，并检验这些影响在经济危机之前、期间和之后是否存在变化。我们发现，扩张效应非常复杂，并且在不同的经济周期和国家群体中存在显着差异。特别是欧盟的东扩对新加入者产生了巨大而积极的影响，而这些影响在金融危机和随后的欧元危机之后却被抑制了。在此期间，2004年的东扩立即对现任成员造成了负面冲击，危机进一步加剧了这种冲击。随后，进入者的恢复超出了危机前的水平，到 2019 年人均收入增长了约 14%，其中波兰成为明显的赢家。与此同时，现任者的人均收入平均下降了约 9%。虽然我们的研究结果在很大程度上支持了这样的观点：进入者是途中为了赶上现任同行，正式β-利用收敛性分析观察到的和综合数据直观地证实，欧盟一体化使半衰期缩短了 50%。