Strong moves on most opex weeks will often be followed by a pullback the following week. This can be seen in the study below, which I have shown a number of times over the years in the Subscriber Letter.

The stats suggest a short-term downside edge. Four days out the SPX has closed lower more than 2/3 of the time, and the losers have been a little larger than the winners on average. Traders may want to remain aware of the strong possibility of a pullback this week.

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