Online sales made up almost a fifth of total retail turnover in 2020, according to findings from the United Nations published on Monday.

As global lockdowns were implemented to tackle the spread of Covid-19, online sales accounted for 19% of overall retail sales last year, a rise from 2019’s figure of 16%, as per estimates from the UN Conference on Trade and Development (UNCTAD) based on major economies’ national statistical offices.

The highest share was reported in South Korea at 25.9%, Reuters reports, a rise from the previous year’s 20.8%. Next was China with a 24.9% share, followed by the UK with 23.3% and the U.S. with 14.0%.

In addition, global e-commerce sales increased 4% to $26.7 trillion in 2019, according to UNCTAD, from the most recent available estimates.

This comprised of business-to-business and business-to-consumer sales, equal to 30% of global economic output in 2019.

Data for the top 13 e-commerce companies, 11 of which are in China and the United States, revealed steep drops in gross merchandise volume for travel and ride-hailing firms.

The report stated: “For instance, Expedia fell from 5th place in 2019 rankings to 11th in 2020, Booking Holdings from 6th to 12th and Airbnb, which launched its initial public offering in 2020, from 11th to 13th.”

At the top of the gross merchandise volume rankings was China’s Alibaba followed by Amazon in the U.S.

Despite the declines at services firms, gross merchandise volume for the top 13 business-to-consumer sales companies increased by 20.5% to $2.9 trillion last year, surpassing the 17.9% rise in 2019.