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Chart Interpretation

# 40-Week Cycle Length

Tom,
I was wondering if you could clear up some confusion for me re: 40-week cycles.
Looking at your latest 20/40 week cycle chart, you show a 40-week bottom on 5/17/05 (Tuesday) followed by the next cycle bottom at 2/8/06 (Wednesday). However, if you count 40 weeks off on the calendar beginning with 5/17/05, the next calendar 40 week end would be 2/20/06.  2/8/06 is only 37 weeks and one day.
I’m trying to lay out my calendar into the future so that I know when these cycles are going to hit.
What am I doing wrong?

It is a confusing piece of language that is responsible for the conflict, and you are justified in being confused about this.

What we refer to as the 40-week cycle is not necessarily exactly 40 weeks in length.  It is also called the 9 month cycle by some. Currently, the important lows which we attribute to this cycle are really running at about 37 weeks between lows (185 trading days).

Our problem lies in the fact that it has been referred to as "the 40-week cycle" for so many years that if we were to start calling it by some other name, then people might think we were talking about a different cycle.  But that is balanced poorly against the problem you bring up, which is that the period does not match the name quite precisely.  I suppose that we should do our part to make sure that we elaborate more completely about the actual period whenever we refer to it.

Thanks for posing a good question.