Factbox: The 1987 Crash, by the numbers

(Reuters) - It was 25 years ago today that the market experienced its worst day in history, as the Dow Jones Industrial Average .DJI slumped by 508 points, or 22 percent.

The 1987 Crash, also known as “Black Monday,” is famously now known as a buying opportunity. The Dow industrials recovered in two years to reach previous highs reached in August 1987.

Despite several rough periods for markets since, most notably the 2008-2009 financial crisis and the bursting of the 2000 dot-com bubble, the sheer magnitude of the one-day fall hasn’t been approached.

Now, if a 22-percent decline were to occur, trading would be halted on the New York Stock Exchange for at least one hour and possibly for the rest of the day, depending on what time such a plunge occurred.

Here are some facts about the market then and now:

Black Monday One-Day DJIA Point Loss: 508 points

Worst One-Day DJIA Point Loss: 777.68 points (September 29, 2008)

Percentage Loss on October 19, 1987: 22.61 percent

Second-Worst Percentage Loss: 7.87 percent (October 15, 2008)

Dow Intraday Loss on May 6, 2010 “Flash Crash”: 1,010.14 points

S&P 500 Percentage Gain, 10/19/87-10/18/12: 548 percent

Apple Inc Percentage Gain: 6,829 percent

U.S. 10-year Treasury yield, 10/19/87: 10.07 percent

U.S. 10-year Treasury yield, current: 1.80 percent

Largest Company by Market Valuation: IBM ($63.02 billion)

Market Value Lost By IBM on 10/19/87: $18.8 billion

Current IBM Market Value: $223 billion

Apple Market Value, 10/19/87: $4.58 billion

Current Apple Market Value: $589.69 billion

Average Daily NYSE share volume in 1987: 189 million

Average Daily NYSE share volume in 2012: 1.36 billion

Average Price of an NYSE Seat in 1987: $1.15 million, then a record

Average Price of an NYSE Seat in 2005, the year seat sales ended after the exchange became a publicly traded company: $3.55 million

#1 Movie in America, October 16-22, 1987: Fatal Attraction

Most Watched TV Show: The Cosby Show

Billboard Top Single, Week ended October 24: Bad, Michael Jackson

Average Retail Price of Gasoline: 86 cents/gallon ($1.50 in 2011 dollars)

Average Retail Price of Gasoline, 2011: $3.53/gallon

Sources: Thomson Reuters, Standard & Poor’s, NYSE Euronext,, US Energy Dept, Billboard, Nielsen

Reporting By David Gaffen; editing by Andrew Hay