For this quantitative exercise, I compared the size and counts of up and down days (SPY cls-cls) from the Museum of Drift period (10/05-10/06) with the most recent period (10/07-10/08).

(Using a 2-sample T-test to compare means of up days with means of abs[down days]):

Note that in the former period the size of up and down days were identical, so this up market was due to 1.23 up days for every down day. In the recent interval (i.e. over the past year) the count of up to down days is 1:1, and the down days are down more than up are up (though not stat. significant).

So if you count on drift for change you need, before you would likely get it by waiting a few days. But now that we need even more change (to pay taxes), the longer you invested the more change you will need.

Alex Castaldo calls attention to the obvious:

Also interesting is that in the former period the typical move was about 0.5%, in the more recent period it has more than doubled  to 1.2% or 1.5% respectively.





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