The stock market crash of October 19, 1987 was the largest one day stock market crash in history. The Dow Jones Industrial Average (DJIA) dropped by 508 points to 1739 (22.6%) of its value or $500 billion dollars.
In financial markets, Black Monday is the name given to Monday, October 19, 1987 crash

Black Monday’s effects were felt across the world, including Canada.

Hong Kong 45.8%
Australia 41.8%
Spain 31%
United Kingdom 26.4%
Canada 22.5%.

Potential causes for the decline include program trading, overvaluation, illiquidity, and market psychology

You Tube Clip - Crash of 1987

Following is the time line of sensex rise in Indian stock market history. We reported similar milestone history when sensex hit 17,000 points.

It just took8 trading days to hit 18,000 from the 17,000 mark.

1000, July 25, 1990
2000, January 15, 1992
3000, February 29, 1992
4000, March 30, 1992
5000, October 8, 1999
6000, February 11, 2000
7000, June 20, 2005
8000, September 8, 2005
9000, November 28, 2005
10,000, February 6, 2006
11,000, March 21, 2006
12,000, April 20, 2006
13,000, October 30, 2006
14,000, December 5, 2006
15,000, July 6, 2007
16,000, September 19, 2007
17,000, September 26, 2007
18,000, October 09, 2007

There are three main practices that can help you ensure the best diversification:

1. Spread your portfolio among multiple investment vehicles such as cash, stocks, bonds, mutual funds and perhaps even some real estate.
2. Vary the risk in your securities. You’re not restricted to choosing only blue chip stocks. In fact, it would be wise to pick investments with varied risk levels; this will ensure that large losses are offset by other areas.
3. Vary your securities by industry. This will minimize the impact of industry-specific risks.

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Inflation is defined as a sustained increase in the general level of prices for goods and services. It is measured as an annual percentage increase. As inflation rises, every dollar you own buys a smaller percentage of a good or service.

* Deflation is when the general level of prices is falling. This is the opposite of inflation.