Mark Zuckerberg, founder and CEO of Facebook, topped the ranking of the top 10 self-made billionaires under 40 once again, according to the latest Hurun "Global Forty-and-Under Self-Made Billionaires" 2019 list. This is the fourth time that the Hurun Research Institute has released the list.

Rupert Hoogewerf, Chairman and Chief Researcher of the Hurun Report, said that Mark Zuckerberg will still be the most successful young entrepreneur in the world for the next 6 years.

Huang Zheng, founder and CEO of the Chinese online group discounter Pinduoduo, is a new comer to the list and claimed the second spot. A total of three Chinese billionaires appeared on the top 10 list.

The report includes 46 self-made billionaires under 40 around the world. The United States took the first place with 21 entrepreneurs, followed by China with 16 entrepreneurs.

Around 77 percent of young billionaires come from the technology industry.

Let's take a look at the top 10 self-made billionaires under 40 in 2019:

10. Adam Neumann

Wealth: US$6.56 billion

Wealth change: 103%

Company: WeWork

Age: 39

Age when net worth hit $1 billion: 35

Time taken to make $1 billion: 5 years

Country of residence: US