Which stock exchange suffered the biggest percentage fall on Black Monday in 1987?

The Hong Kong Stock Exchange suffered the biggest percentage fall on Black Monday in 1987.

Hong Kong’s stock market fell about 45.8 percent during the crash period, making it one of the most severely affected major markets. The collapse began internationally in October 1987 and spread rapidly through financial centers in Asia, Europe, and North America. Hong Kong’s decline was especially severe because its market had risen strongly and was vulnerable to abrupt changes in investor confidence.

The United States received the greatest attention because the Dow Jones Industrial Average fell 22.6 percent on October 19, the largest one-day percentage drop in its history. However, comparing markets across the entire episode shows that Hong Kong experienced an even larger percentage decline.

Exchange trading calendars and reporting conventions can produce slightly different figures. The key historical comparison is that Hong Kong’s market suffered the largest percentage collapse among the major exchanges during the 1987 event.