The plunge was mainly attributable to a 75.6 percent drop in international passenger traffic, according to data from the International Air Transport Association.

Demand for business trips and tourism tumbled after many countries imposed entry bans or requested self-quarantine to curb the spread of the novel coronavirus.

The impact of the pandemic was less harsh on domestic passenger traffic, which dropped 48.8 percent, IATA said.

"Last year was a catastrophe. There is no other way to describe it," Alexandre de Juniac, director general of IATA, said in a recent release. "The situation turned dramatically worse over the year-end holiday season, as more severe travel restrictions were imposed in the face of new outbreaks and new strains of COVID-19."

By region, the sharpest fall in 2020 international and domestic passenger traffic was 72.2 percent in the Middle East, followed by declines of 69.6 percent in Europe and 68.8 percent in Africa.

The Asia-Pacific region was least hit, even though passenger demand sagged 61.9 percent last year, according to IATA, which represents around 290 airlines that account for 82 percent of global air traffic.

IATA expects global passenger demand in 2021 to improve to 50.6 percent of levels in 2019, the year before the pandemic. But a downside risk remains if more severe travel restrictions in response to new variants of the virus remain in place.

Passenger demand could only hit 38 percent of 2019 levels in 2021 if such a risk scenario materializes, the association said.

IATA said last July that global air traffic would not return to levels seen prior to the pandemic until 2024.