The Impact of ESG Scores on Firm Performance: A Comparison of the European Market Before and After the 2008 Financial Crisis

Abstract: This study explores the impact of ESG Scores on firm performance and seeks to establish whether the impact increased since the 2008 financial crisis. This is done by performing regressions on ESG Scores, and the respective pillars of Environmental, Social, and Governance, and firm performance, measured as both accounting-based performance, using ROA, and market-based performance, using Tobin’s Q. The study adopts a quantitative approach, utilising a random-effects model to analyse panel data across two sample periods - a pre-crisis period, from 2003-2006, and a post-crisis period, from 2010-2019. In addition, t-tests were performed to see if the impact changed significantly from the pre-crisis to post-crisis period. The study analyses data from 218 firms from the STOXX Europe 600 index, with four smaller sub-samples. The results indicate that ESG Scores have a positive impact on firm performance, with market-based firm performance being significantly correlated both before and after the crisis. Accounting-based performance, however, was only significantly correlated with ESG Scores before the crisis. In addition, the Environmental pillar was positively correlated with both measures of performance before and after the crisis, and the same was true for the Social pillar, except for with post-crisis accounting-based performance. Interestingly, the Governance pillar was not significantly correlated with performance in any of the regressions. Finally, while the average ESG Score among the observed companies increased in the post-crisis period, the impact of ESG performance on firm performance did not change significantly. The results of this study are supportive of the stakeholder theory perspective over the principal-agent theory, and show that ESG performance does indeed positively impact firm performance. Future research could explore whether other events have played a significant role in the rising importance of ESG, or if the results of the present study can be replicated across different time periods and geographical regions.