SPY 84 and 105

There is a good chance that SPY will fill the gap from Monday's gap up, when SPY moved from 89 to 94. Friday's low around 84 and Monday's high around 105 define the range. This doesn't mean that those numbers will define the range, but they are the action numbers to watch.

Other bloggers have written that a gap up usually means more upside, however, most of the time the gap is filled. My thinking is that buying that retracement to the gap is the high percentage play. What if the gap isn't filled? Then I will look for some other high percentage plays.