Environmental efficiency is considered to be a critical pillar of sustainable development; consequently, improving environmental performance has aroused attention at both the local and global level. This study evaluated the environmental performance of European Union (EU) countries using the data envelopment analysis (DEA) approach and the global Malmquist-Luenberger index. Although literature using the DEA approach to measure environmental performance exists, this study's main contribution was considering different types of undesirable outputs and using long-term panel data on EU countries. In particular, the DEA window analysis technique was applied to evaluate the environmental performance of 27 EU countries in cross-sectional and time-varying data during the period 2000–2017. Three DEA models were examined; labor, capital, and energy were used as common inputs with a combination of different outputs, including gross domestic product, carbon dioxide and particulate matter emissions, and waste. The empirical results revealed that the trends in the environmental performance of the entire EU and its individual countries were similar under all examined models. Environmental performance was indeed negatively affected by the financial crisis of 2007–2008; this impact was mainly observed in eastern EU countries. Furthermore, both economic and environmental variables significantly influenced countries' overall efficiency. The analysis using the global Malmquist-Luenberger index elucidated that overall, EU countries experienced the efficiency improvement during the study period, although fluctuations were observed. These results enable countries and policymakers to understand their environmental performance, identify strengths and weaknesses, and set targets for further improvement based on the current best practices of comparable peers.

环境效率被认为是可持续发展的重要支柱；因此，改善环境绩效引起了地方和全球的关注。这项研究使用数据包络分析（DEA）方法和全球Malmquist-Luenberger指数评估了欧盟国家的环境绩效。尽管存在使用DEA方法测量环境绩效的文献，但这项研究的主要贡献是考虑了不同类型的不良产出并使用了欧盟国家的长期面板数据。特别是，DEA窗口分析技术被用于评估2000-2017年期间欧盟27个国家的横截面和时变数据的环境绩效。检验了三种DEA模型；劳动力，资本，能源和能源被用作共同的投入，并结合了不同的产出，包括国内生产总值，二氧化碳和颗粒物排放量以及废物。实证结果表明，在所有检验的模型下，整个欧盟及其单个国家的环境绩效趋势都相似。实际上，环境绩效受到2007-2008年金融危机的负面影响；这种影响主要发生在欧盟东部国家。此外，经济和环境变量都极大地影响了国家的整体效率。使用全球Malmquist-Luenberger指数进行的分析表明，尽管观察到波动，但欧盟国家总体上在研究期间效率有所提高。