pre holiday

SPY opened right on top of a 50% retracement today, as measured from Monday's high to yesterday's low.  I've included the pre-market in this chart below to illustrate how price used this midpoint as a pivot prior to the open.  Also included is a set of Fibs measured off of the PDH to PDL (yellow 50% line), also giving the pre-market a nice S/R pivot to work off of:

While on the Open, using a set of Fibs to measure the PDC to today's Open, price quickly achieved a 100% extension off of today's momentum gap: