People attend the C2H4 catwalk show at London Fashion Week Men's in London, Britain January 6, 2019. (Photo by Henry Nicholls/Reuters)

A villager pours brine into troughs at ancient salt fields on May 5, 2005 in Yantian Village on Hainan Island, China. (Photo by China Photos/Getty Images)

Japanese Yuuka Hasumi, 17, and Ibuki Ito, 17, also from Japan, who want to become K-pop stars, perform at an Acopia School party in Seoul, South Korea, March 16, 2019. Acopia is a prep school offering young Japanese a shot at K-pop stardom, teaching them the dance moves, the songs and also the language. (Photo by Kim Hong-Ji/Reuters)

Visitors wear shirts with an image of former Chinese leader Mao Zedong at the Shanghai World Expo site in Shanghai, May 2, 2010. (Photo by Aly Song/Reuters)

A reveller attends the “Amigos da Onça” street party on the second day of Carnival on February 10, 2024 in Rio de Janeiro, Brazil. (Photo by Buda Mendes/Getty Images)

Singer Ariana Grande performs during the 2014 MTV Europe Music Awards at the SSE Hydro Arena in Glasgow, on November 9, 2014. (Photo by Toby Melville/Reuters)

English heavyweight Joe Joyce celebrates after defeating Christian Hammer during the WBC Silver Silver and WBO International Heavyweight Title fight between Joe Joyce and Christian Hammer at OVO Arena Wembley on July 02, 2022 in London, England. (Photo by Andrew Couldridge/Action Images via Reuters)

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)