that marketplace. A feedback loop of noise-induced-volatility has been cited by some analysts as the major reason for the severe depth of the crash. It does not, however, explain what initially triggered the market break. Moreover, Lawrence A. Cunningham has suggested that while noise theory is "supported by substantial empirical evidence and a well-developed intellectual foundation", it makes only a partial contribution toward explaining events such as the crash of October 1987. Informed traders, not swayed by psychological or emotional factors, have room to make trades they know to be less risky. Resulting regulation After Black Monday, regulators overhauled trade-clearing protocols to bring uniformity to all prominent market products. They also developed new rules, known as "trading curbs" or colloquially as circuit breakers, allowing exchanges to temporarily halt trading in instances of exceptionally large price declines in some indexes; for instance, the DJIA. These trading curbs were first used multiple times during the 2020 stock market crash. See also 2010 Flash Crash List of largest daily changes in the Dow Jones Industrial Average Wall Street Crash of 1929 (Black Tuesday) Black Monday (TV series) Black Monday (2020) Footnotes References Sources . Further reading External links CNBC Remembering the Crash of 1987 Black Monday photographs 1987 in New York City 1987 disasters 1987 in economics Economic crises in the United States Financial crises Stock market crashes 1987 in international relations Monday October 1987 events in the United States