Triple Witching

DJ 30

Notice the four super high volume days in the chart? I always knew it was due to options expiration, but I only just realized these four days occur on days of triple witching. According to Investopedia this is an event that occurs when the contracts for stock index futures, stock index options and stock options all expire on the same day. Triple witching days happen four times a year on the third Friday of March, June, September and December.

As such, traders using volume analysis might want to interpret the volume on these days with a pinch of salt. Just scroll through some stocks and you'll notice this disgustingly high volume on them too. Interesting huh?