Editing Triple witching hour (section)

{{Short description|Term in stock market trading}}
'''Triple witching hour''' is the last hour of the [[stock market]] trading session (3:00–4:00{{nbsp}}p.m., [[Eastern Time|New York time]]) on the third Friday of every March, June, September, and December.  Those days are the expiration of three kinds of securities:
* [[Stock market index future]]s;
* [[Stock market index option]]s;
* [[Stock option]]s.

The simultaneous expirations generally increases the trading volume of options, futures, and their underlying stocks, occasionally increasing the [[Volatility (finance)|volatility]] of prices of related securities.

On those same days [[single-stock future]]s also expire, so that the final hour is sometimes referred to as the '''quadruple witching''' hour.<ref>{{cite web|title=Quadruple Witching |url=http://www.investopedia.com/terms/q/quadruplewitching.asp |publisher=Investopedia}}</ref>