Black Monday: Definition in Stocks, What Caused It, and Losses

What Was Black Monday?

Black Monday occurred on Oct. 19, 1987, when the Dow Jones Industrial Average (DJIA) lost almost 22% in a single day. The event marked the beginning of a global stock market decline, and Black Monday became one of the most notorious days in financial history. By the end of the month, most of the major exchanges had dropped more than 20%.

Economists have attributed the crash to a combination of geopolitical events and the advent of computerized program trading that accelerated the selloff.

Key Takeaways

  • Black Monday refers to the stock market crash that occurred on Oct. 19, 1987 when the DJIA lost almost 22% in a single day, triggering a global stock market decline.
  • The SEC has built a number of protective mechanisms, such as trading curbs and circuit breakers, to prevent panic-selling.
  • Investors can take pre-emptive steps in order to deal with the possibility of a stock market crash, similar to Black Monday, happening again.

Black Monday

Causes of Black Monday

The cause of the massive stock market drop cannot be attributed to any single news event since no major news event was released the weekend preceding the crash. However, several events coalesced to create an atmosphere of panic among investors.

  • A strong bull market overdue for a correction: One of the main factors that drove the Black Monday crash was a strong bull market that was overdue for a major correction in prices since 1982. Stock prices had since then tripled in value.
  • Program Trading: The trade deficit of the United States widened with respect to other countries. Computerized trading, which was still not the dominant force it is today, was increasingly making its presence felt at several Wall Street firms. The stock market crash of 1987 revealed the role of financial and technological innovation in increased market volatility. In automatic trading, also called program trading, human decision-making is taken out of the equation, and buy or sell orders are generated automatically based on the price levels of benchmark indexes or specific stocks. Leading up to the crash, the models in use tended to produce strong positive feedback, generating more buy orders when prices were rising and more sell orders when prices began to fall.
  • Portfolio Insurance: Portfolio insurance is a program trading strategy that seems to be one of the key factors at the center of Black Monday. The strategy is aimed to hedge a portfolio of stocks against market risk by short-selling stock index futures, thus limiting the potential losses if stocks decline in price, without having to sell off those stocks. The computer programs began liquidating stocks as certain loss targets were hit, pushing prices lower. This led to a domino effect as the falling markets triggered more stop-loss orders, while bids stopped.
  • Mass Panic: Crises, such as a standoff between Kuwait and Iran, which threatened to disrupt oil supplies, also made investors jittery. The role of media as an amplifying factor for these developments has also come in for criticism. While there are many theories that attempt to explain why the crash occurred, most agree that mass panic caused the crash to escalate.

Can It Happen Again?

Since Black Monday, a number of protective mechanisms have been built into the market to prevent panic selling, such as trading curbs and circuit breakers. However, high-frequency trading (HFT) algorithms driven by supercomputers move massive volumes in just milliseconds, which increases volatility.

The 2010 Flash Crash was the result of HFT gone awry, sending the stock market down 10% in a matter of minutes. This led to the installation of tighter price bands, but the stock market has experienced several volatile moments since 2010.

Amid the 2020 global crisis, markets lost similar amounts in the month of March as jobless rates reached their highest levels since the Great Depression, before recovering over the summer of that year.

Lessons From Black Monday and Other Market Crashes

A market crash of any duration is temporary. Many of the steepest market rallies have occurred immediately following a sudden crash. The steep market declines in August 2015 and January 2016 were both roughly 10% drops, but the market fully recovered and rallied to new or near new highs in the following months.

Stick With Your Strategy

A well-conceived, long-term investment strategy based on personal investment objectives should provide the confidence for investors to remain steadfast while everyone else is panicking. Investors who lack a strategy tend to let their emotions guide their decision-making.

Buying Opportunities

Knowing that market crashes are only temporary, these times should be considered an opportunity to buy stocks or funds. Market crashes are inevitable. Savvy investors have a shopping list prepared for stocks or funds that would be more attractive at lower prices and buy while others are selling.

Turn Off the Noise

Over the long term, market crashes such as Black Monday are a small blip in the performance of a well-structured portfolio. Short-term market events are impossible to predict, and they are soon forgotten. Long-term investors are better served by tuning out the noise of the media and the herd and focusing on their long-term objectives.

What Caused Black Monday 1929?

Oct. 28, 1929, is also referred to as Black Monday. It was the first Monday after Black Thursday, which On that day, stocks fell by 12.82%. A few days earlier, on Black Thursday, stocks had already experienced a decline of 11%. This precipitated the stock market crash of 1929. Other causes of the crash were low wages, increasing debt, a struggling agricultural sector, and an excess of large bank loans that could not be liquidated.

Did People Lose Money on Black Monday?

Yes. Black Monday caused about $500 billion in losses when the Dow Jones Industrial Index fell 508 point. That was, at that time, the biggest-ever one-day stock-market loss.

Why Is It called Black Monday?

Black Monday refers not only to the events on Oct. 19, 1987, but also to a number of specific Mondays when sudden, severe, and turbulent events have occurred, from military battles to massacres and stock market crashes. The term seems to have been coined by U.S. Representative John Bell Williams on the floor of Congress in Washington, D.C. on Monday, 17 May 1954. This was the date of the Supreme Court's decision in Brown v. Board of Education, in which the Court ruled that U.S. state laws establishing racial segregation in public schools were unconstitutional. In opposition to the decision, white citizens' councils were formally organized throughout the south to preserve segregation and defend segregated schools.

The Bottom Line

Black Monday refers to the catastrophic worldwide stock market crash on Oct. 19, 1987, when the DJIA fell 508 points, or 22.6%, in a single day (the largest one-day decline ever). Other major stock markets saw similarly huge declines.

Stock markets quickly recovered a majority of their Black Monday losses. In just two trading sessions, the DJIA gained back 288 points, or 57%, of the total Black Monday losses. In less than two years, US stock markets had surpassed their pre-crash highs.

Since then, the U.S. Securities and Exchange Commission has built a number of protective mechanisms to avoid market panic, such as trading curbs and circuit breakers.

Article Sources
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  2. The United States Department of Justice. "Future Trader Pleads Guilty to Illegally Manipulating The Futures Market in Connection With 2010 Flash Crash."

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