Some are in it just for the money, others to help buy a meal. Then there are those who trade for fun or to spend time among friends. Millions of investors – pensioners, security guards, high-school students – dominate China's stock markets, conducting about 80 percent of all trades. Retirees gather in brokerage houses dotted around China also to enjoy some company and savour the air conditioning on hot days. Some start as young as 13, trading from home with an eye on future careers in finance. Winning isn't guaranteed. This year, among the most turbulent in China's financial history, its stock markets more than doubled in the six months to May, only to crash amid concerns that growth in the country, which makes everything from cars to steel, is slowing faster than previously thought. (Photo by Aly Song/Reuters)

Models promote a condom brand at the first Shenzhen s*x Culture Festival on September 21, 2007 in Shenzhen of Guangdong Province, China. The festival aims to increase awareness about reproductive health and popularise s*x education. (Photo by China Photos/Getty Images)

Rescuers work at the accident scene on a bridge on July 24, 2011 in Wenzhou, Zhejiang Province of China. The train from Hangzhou to the city of Wenzhou derailed on a bridge that is 10 m above the field in Shuangyu Town of Wenzhou city at 8:34 p.m on Saturday. The first four coaches and the 15th and 16th coaches of the train went off the line killed 32 and injured 191 people. (Photo by ChinaFotoPress/Getty Images)

A Chinese girl peeps at Santa at a shopping center on Christmas Eve December 24, 2011 in Beijing, China. Though Christmas is not officially celebrated in China, the holiday is becoming increasingly popular as Chinese adopt more Western ideas and festivals. (Photo by Feng Li/Getty Images)

A Chinese tourist wears protective gloves as she holds a baby Siberian tiger as they pose for pictures at the Heilongjiang Siberian Tiger Park on August 16, 2017 in Harbin, northern China. The center is one of two Siberian tiger parks in the Chinese province of Heilongjiang, about 500 kilometers (300 miles) from the border with Russia. It is considered the world's largest for breeding the Siberian, or Amur, tiger which is listed as endangered by the World Wildlife Federation. (Photo by Kevin Frayer/Getty Images)

A man performs a split as he practices Kung Fu at Beihai Park in Beijing, China August 20, 2017. (Photo by Reuters/China Stringer Network)

People fight for the ball as they take part in a mud football match during a festival for celebrating harvest in a village in Jinhua, Zhejiang Province, China September 24, 2017. (Photo by Reuters/China Stringer Network)

People dance in a park on a foggy day in Huai'an, Jiangsu province, China October 10, 2017. (Photo by Reuters/China Stringer Network)