The first trading day of extreme losses in Hong Kong during the 1987 stock market crash was called Black Monday.
Hong Kong’s market began the international chain of major declines on October 19, 1987, before the same date became associated with Wall Street’s historic collapse. The Hang Seng Index fell sharply, and trading was later suspended for several days as officials and market participants tried to restore order.
The panic then spread through international exchanges. Markets in Europe and North America suffered major losses, culminating in the Dow Jones Industrial Average’s 22.6% fall. The episode demonstrated how increasingly connected financial markets could transmit fear across time zones.
The name Black Monday is sometimes used only for the New York crash, but it can also describe the global market event that began in Hong Kong. Context matters: several markets experienced their own Black Monday sessions on October 19, and local percentage losses differed substantially.