David Callaway, CEO of TheStreet (TST) , was a reporter at The Boston Herald newspaper during the time of the 1987 Black Monday crash.

"It was certainly a day I'll never forget," he said. 

The Dow Jones Industrial Average fell 508 points on October 19, 1987 to 1,738.74.

"A fall like that of 500 points then was like 5,000 points today," he said. "Can you imagine if the market fell 5,000 points in one day?"

Callaway pointed to the complexity of financial markets today, compared to 1987, which now contain dark pools.

"Back then there was the New York Stock Exchange, the American Stock Exchange, the Nasdaq and a couple of regional exchanges," he said. "Now, there are so many different places to trade."

Crash of '87 - TheStreet Special Report

Black Monday made headlines 30 years ago today. Check out our full Crash of '87 Special Report for the ultimate #TBT:

Originally published Oct. 19.