by Heera Rajavel
Abstract
On January 28, 2019, the S&P Dow Jones Indices launched the ESG S&P 500 Index, aiming to create a sustainable index fund with a similar risk/return profile to the S&P 500 Index. This study assesses the causal mechanisms behind the performance of the S&P 500 ESG Index by running two difference-in-differences estimations using a panel data set of 698 companies. The first difference-in-differences estimation compares the stock prices of companies on the S&P 500 ESG Index to the stock prices of companies S&P 500 Index, determining if companies on the S&P 500 ESG Index received an “ESG label” price premium. Results show that in the short-term and the long-term, companies on the S&P ESG 500 Index experienced statistically significant negative stock price growth relative to companies only on the general S&P 500 Index; the “ESG label” appears to slow stock growth for companies on the S&P 500 ESG Index by $48.24 in the short-term and $65.29 in the long-term. The second difference-in-differences estimation compares the stock prices of companies on the S&P 500 ESG Index to the stock prices of companies with similar ESG qualifications that are not on an S&P Index, determining if companies in the S&P 500 ESG Index received an “S&P label” price premium. These results found that in both the short and the long run, companies on the S&P 500 ESG Index faced statistically significant positive stock price growth relative to companies with similar ESG qualifications; the “S&P label” seems to increase stock price growth for companies on the S&P 500 ESG Index by $2.19 in the short-term and $7.63 in the long term.
Professor Lawrence Kreicher, Faculty Advisor
Professor Michelle Connolly, Faculty Advisor
JEL Codes: G2, G23, Q56
