On Monday, October 19th 1987, an event known as Black Monday happened.

This was a stock market crash that first started in Hong Kong,, before spreading to other countries. In the United States, the Dow Jones Industrial Average fell 508 points, or 22.61%. This was the largest one day decline in the DJIA.

The world stock markets had seen enormous growth throughout the year to that point. The cause of the crash is somewhat debated; one reason for the US crash was the Savings and Loan Crisis in the United States that started in the previous year, after the Tax Reform Act of 1986. Another area that received a lot of blame was the computerised selling by program traders; such a thing being relatively new at the time.

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