During the 1987 Black Monday crash, which market recorded the largest one-day percentage fall?

During the 1987 Black Monday crash, the Hong Kong Stock Exchange recorded the largest one-day percentage fall among major markets.

Hong Kong’s Hang Seng Index plunged 45.8% during the October 1987 crash. The fall was considerably larger in percentage terms than the approximately 22.6% decline in the Dow Jones Industrial Average on October 19. Trading on Hong Kong’s exchange was suspended for several days as authorities and market participants dealt with the turmoil.

The shock moved across time zones. Markets in Asia reacted before Europe and North America opened, while London and New York then suffered major losses. The episode demonstrated how closely linked large financial centres had become.

The answer refers to the Hong Kong market, often represented by the Hang Seng Index, rather than to a particular listed company. It is also distinct from the question of which market reopened first after the crash.