The Outbreak of COVID-19 and Stock Market Responses: An Event Study and Panel Data Analysis for G-20 Countries

This study examines the impact of the COVID-19 outbreak on the stock markets of G-20 countries. We use an event study methodology to measure abnormal returns (ARs) and panel data regression to explain the causes of ARs. Our sample consists of indices in G-20 countries. The observed window comprises 58 days post the COVID-19 outbreak news release in the international media, and the estimation window consists of 150 days before the event date. We find statistically significant negative ARs in the four sub-event windows during the 58 days. Negative ARs are significant for developing as well as developed countries. The findings of this study reveal that cumulative average abnormal return (CAAR) from day 0 to day 43, ranging from –0.70 per cent to –42.69 per cent, is a consequence of increased panic in the stock markets resulting from an increased number of COVID-19 positive cases in the G-20 countries. From day 43 to day 57, CAAR ranging from –42.69 per cent to –29.77 per cent indicates the recovery of stock markets after a major stock price correction due to COVID-19. Additionally, the results of panel data analysis confirm the recovery of stock markets from the negative impact of COVID-19.