What is Abnormal Returns

This chapter investigates the financial performance of airline companies and proposes a harmonic index to state a performance ranking for the COVID-19 era covering the years 2018, 2019, and 2020. All data required for this study were obtained from the Thomson-Reuters database. A total number of 111 airlines are reached and listed by total assets. The 20 biggest airlines by total assets in 2020 are chosen for this study. A harmonic index is constructed by using performance indicators for profitability, liquidity, and efficiency. Then, the biggest 20 airlines are ranked by the harmonic index values for the COVID-19 era. The results revealed that North America and European-based airlines performed very badly in 2020 compared to pre-COVID years while Far East-based airlines were able to manage the pandemic year much better.