Photo taken on July 17, 2020 shows an office of online marketplace Pinduoduo in east China's Shanghai. Photo: Xinhua

Chinese e-commerce firm Pinduoduo's fourth-quarter revenues surged 146 percent year-on-year, primarily due to an increase from online marketing services and contributions from merchandise sales, the company said in an earnings report released on Wednesday.

Total revenues for fiscal year 2020 increased 97 percent, and excluding contributions from merchandise sales, total revenues grew 78 percent.

Annual active users hit 788 million last year, surging from 582 million in 2019, overtaking bigger domestic e-commerce rival Alibaba, which had 779 million active buyers during the same period. 

Pinduoduo thus became the No.1 e-commerce group in China in terms of buyers.

The annual consumption per active user rose 23 percent to 2,115.2 yuan ($325).

Gross merchandise volume in 2020 was 1.667 trillion yuan, up 66 percent.

Agricultural products and agricultural sideline products became the fastest-growing categories on the platform during the coronavirus-plagued 2020 when domestic consumption was hit. 

In 2020, Pinduoduo's agricultural and sideline products turnover doubled to 270 billion yuan, accounting for 16.2 percent of annual turnover, much higher than the industry's average of about 3 percent.

"Pinduoduo started with agricultural products, with the vision of offering consumers the 'Costco + Disney' experience of more savings and more fun. We are now the largest agriculture platform in China and we hope that Pinduoduo can one day become the largest grocer in the world," CEO Chen Lei said.

"Agriculture is a strategic priority for us, and we will continue to invest in technology and operations across the agricultural value chain to optimize food production, distribution and consumption," added David Liu, vice president of strategy. "Reducing inefficiencies in the supply chain will lower structural costs and make groceries more affordable for everyone."

Shares of NASDAQ-listed Pinduoduo rose over 6 percent following the release of the results in pre-market trading but then started tumbling. They were down by 4.84 percent as of press time.

The 2020 net loss was 7.18 billion yuan, higher than market expectations of 6.67 billion yuan and also more than 6.97 billion yuan in 2019.

Along with the financial results, Zheng Huang, founder and chairman of board of directors, said in a letter to shareholders that he had stepped down from the board, and CEO Chen would become chairman.

Huang said he will pursue lifelong interests and devote himself to research in the fields of food science and life science.