Which Chinese stock index lost about one-third of its value during the 2015 stock-market crash?

The Shanghai Composite lost about one-third of its value during the 2015 Chinese stock-market crash.

The index had more than doubled between mid-2014 and June 2015, fueled by retail investor participation, margin borrowing, and expectations of continued economic growth. It peaked on June 12, 2015, before a rapid sell-off began.

By early July, the Shanghai Composite had fallen by roughly 30% from that peak. Chinese authorities responded with measures including trading halts, restrictions on some share sales, support for major stocks, and investigations into market activity. The Shenzhen market and other Chinese assets also experienced severe turbulence.

The Shanghai Composite tracks many companies listed on the Shanghai Stock Exchange. It is not the same as the Hang Seng Index, which represents Hong Kong-listed shares, or the Shenzhen Component Index. The 2015 episode is also called the Chinese stock-market turbulence of 2015–2016 because volatility continued after the initial crash.