January op-ex week has been a tough week for the market since 1999. Interesting about January op-ex week is that it often occurs in conjunction with Martin Luther King Day. Below is a list of the last 13 January op-ex weeks with their performance results. Note that some of these weeks contained four trading days and some contained five. In either case the market was assumed to have been “bought” the Friday before op-ex Friday and “sold” on op-ex Friday.
As you can see there has been a decided downside tendency over the last 13 years. The drawdown / run-up stats at the bottom are especially compelling for the bears.