A woman holds up what the Chris Steaks & Burgers restaurant says is Thailand's biggest burger weighing more than 6 kilograms, before a competition held to eat it at the restaurant in Bangkok, Thailand, October 11, 2019. Chris Steaks and Burgers is offering a 10,000 baht ($330) prize for anyone who can finish the mammoth snack in nine minutes – one baht for every calorie. (Photo by Jiraporn Kuhakan/Reuters)

An oversized, prehistoric praying mantis wreaks havoc in a freeway underpass as it overturns cars and trucks, in a film still from “The Deadly Mantis”, directed by Nathan Juran, 1957. (Photo by Universal Pictures/Courtesy of Getty Images)

Flowers and an iPad showing a picture of Steve Jobs are placed at a makeshift memorial for Steve Jobs at the Apple headquarters on October 5, 2011 in Cupertino, California. Jobs, 56, passed away after a long battle with pancreatic cancer... (Photo by Kevork Djansezian/Getty Images)

Demonstrators throw fire bombs to riot police during violent protests in central Athens February 12, 2012. (Photo by Milos Bicanski/Getty Images)

Deputies of the opposition fight with deputies of the majority for a second time in two days, during the second session of the newly elected Ukrainian parliament in Kiev on December 13, 2012. (Photo by Sergei Supinsky/AFP Photo)

A little girl takes a picture of a lion in the zoo in Frankfurt, Germany, Tuesday, September 13, 2016. (Photo by Michael Probst/AP Photo)

A man dressed as Mr. Destructoid checks his mobile phone while gamers play a game at the 2014 Electronic Entertainment Expo, known as E3, in Los Angeles, June 10, 2014. REUTERS/Jonathan Alcorn

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)