BEIJING (CHINA DAILY/ASIA NEWS NETWORK) - The number of the rich under the age of 40 increased to 53, up seven from last year, with the average wealth reaching US$5.2 billion (S$7.2 billion), according to Hurun's latest list of global 40-and-under self-made billionaires.

Among these, 20 are from the United States and 19 from China, accounting for more than 70 per cent of the world's known young billionaires. There were 18 newcomers to the list.

Mr Mark Zuckerberg, social network Facebook's founder and chief executive officer, tops the list with his wealth hitting US$84 billion, a rise of US$4 billion from last year, followed by Chinese billionaires Huang Zheng, founder of Pinduoduo, and Zhang Yiming, chairman of ByteDance, with their wealth at US$18 billion and US$13.8 billion, respectively.

Also on the list, from Singapore, are Facebook co-founder and angel investor Eduardo Saverin, 37, at No. 5 with US$12 billion, and 39-year-old Ye Gang, who co-founded online gaming and e-commerce firm Sea, in the 36th position with wealth worth US$1.6 billion.

There were two women on the list: Ms Kylie Jenner from Kylie Cosmetics and Ms Wu Yan from Hakim Unique Internet Co.

Ms Jenner, at age 22, is also the youngest billionaire, at 46th spot with US$1.1 billion.

These billionaires are mainly from e-commerce (eight), social media (seven), shared economy (six) and online games (five).

Beijing ties with San Francisco in the number of under-40 self-made billionaires, with both having 11 in total.

Additional reporting by The Straits Times