Which stock exchange experienced the first major plunge during the worldwide Black Monday crash of October 1987?

The Hong Kong Stock Exchange experienced the first major plunge during the worldwide Black Monday crash of October 1987.

Hong Kong’s market began the global sequence of dramatic declines on October 19, 1987, local time. The Hang Seng Index fell 11.1% that day, and trading was later suspended for several days as authorities and market participants tried to contain disorder.

The selling then spread westward through international markets. European exchanges recorded steep losses, and the New York Stock Exchange suffered its historic 22.6% one-day percentage decline. Australia and other markets were also affected, demonstrating how trading hours could transmit shocks across time zones.

The phrase “Black Monday” is most strongly associated with New York’s October 19 session, but the Hong Kong move came earlier in the worldwide chain. This timing is why accounts of the crash distinguish the first major plunge from the U.S. record-setting collapse.