COVID-19 is referred to as an exogenous shock that has affected the functioning of global economies. One consequence of the emergence of the lethal SARS-CoV-2 virus was panic in the capital markets. This event inspired research aimed at assessing the situation on the stock exchanges in the first quarter of 2020, with particular emphasis on the period of the market downturn caused by the pandemic. In particular, the researchers sought answers to the question of when the dramatic sell-off of stocks on global stock exchanges began, how long did it last, when did it end, and by how much did the major global stock indices drop during that time. Historical quotations of 44 major world stock exchange indices were analyzed. For each of them, the starting and ending dates of the downward trend were determined, and then the dynamics indicators were calculated, showing changes in the decreases of indices in percentage terms. The European, Asian, North and South American and Australian markets were analyzed. As a result of the research, it was found that in about one month of the stock market panic, the indices lost about a third of their initial value, with the scale of declines being greater in Europe, North and South America and Australia (average changes at the level of approx. -36, -37 percent), while in Asia the duration of the bear market was less clear-cut and was characterized by a decline in the main indices by an average of 31 percent. In the course of the research it was found, inter alia, that the declines recorded during the Great Depression and the Financial Crisis of 2008 lasted not only longer, but were also much larger compared to the crisis of 2020. The conclusions from the research indicate very clearly the feature of modern capital markets - stock market valuations of companies are unstable and strongly dependent on the turmoil in the external environment.