Which Chinese stock-market benchmark lost about one-third of its value between June and August 2015?

The Shanghai Composite lost about one-third of its value between June and August 2015 during China’s stock-market turbulence.

The Shanghai Composite had risen rapidly during the first half of 2015, helped by optimism, margin borrowing, and strong participation by individual investors. It reached a 2015 closing high of 5,178.19 on June 12. Concern about stretched valuations and forced selling then helped drive a steep decline.

The index fell more than 8% on August 24, a day widely known as China’s Black Monday. Additional volatility followed, including another major global sell-off on August 25. Chinese authorities responded with measures such as trading restrictions, support for purchases, and changes affecting initial public offerings.

The Shenzhen Component and Hong Kong’s Hang Seng Index also moved sharply, but they are different benchmarks. The Shanghai Composite tracks shares listed on the Shanghai Stock Exchange and is the index referenced here.