Hong Kong was the first major financial center to crash during Black Monday in October 1987.
The Hong Kong Stock Exchange fell sharply on October 19, 1987, before the trading day reached the United States. The shock then moved westward through international markets, including Australia, Europe, and North America. Because financial centers operated in different time zones, the event appeared as a worldwide sequence of connected sell-offs.
Hong Kong’s Hang Seng Index fell 46% between October 19 and October 26. The exchange was closed from October 20 through October 23 to contain disorder and allow market participants to assess the crisis. When trading resumed, heavy losses continued.
New York’s famous Black Monday session occurred on October 19 in local time and produced the Dow’s record percentage fall. That does not make New York the first market affected. Hong Kong’s earlier trading hours meant it registered the initial major collapse in the global chain.