BEIJING — Unicorns, previously known only to exist in myth or Silicon Valley, are quietly multiplying in China.

According to a report by China's Ministry of Science and Technology and the Great Wall Enterprise Institute (GEI), China was home to 131 unicorns at the end of last year, almost double the number one year before.

Unicorns are privately owned companies valued at over $1 billion, established within the past decade.

Beijing, Shanghai, Shenzhen and Hangzhou are the unicorns' main breeding grounds, though 12 other cities have small populations. Beijing is home to almost half of the total.

The 131 have an average estimated value of $3.7 billion and come from 18 industrial sectors. The combined value of the top seven "super unicorns" is more or less equal to the other 124 put together. Over one third of the companies were established after 2014.

E-commerce, internet finance, intelligent hardware and transportation are the natural habitat of more than half of the unicorns.

Dozens of unicorns frolic in Beijing's Zhongguancun, where multinationals and more than 300 listed Chinese companies are always working on the incarnation of another. On Sunday, Zhongguancun Bank was born: its mission is supporting start-ups and innovation by financing small sci-tech firms.

The break up of large companies is an important source of unicorns. More than 30 of them have broken away from industrial giants such as Alibaba and Tencent. Fourteen on the list, with about 40 percent of the total estimated value, have connections to Alibaba. Tencent incubated 16 with about a quarter of the total value.

From a global point of view, big companies generate unicorns through splitting their business, investment and mergers, which is now the trend in China, said Wang Delu, president of GEI.

According to the report, the sharing, platform and intelligence sectors of the economy are the three areas where unicorns are most likely to flourish.

By exploring the value of idle resources, the sharing economy has established a new business model. The platform economy gathers service providers and seekers, pioneering a future commercial model. With major breakthroughs in big data, virtual reality and intelligent hardware, the intelligence economy is seen as the "next big thing."

"All three areas have a lot of unicorn firms, and more are on the way," the report concluded.