Very interesting day! As you can see from the 15min chart (normal trading hours only) below, we made a perfect 50% pullback and now have a target at 914.50.
After hours, I'm looking for a 50% retracement to 906.75 with the same target as above (follow the arrows). You can also see on the chart below the 914.25 Gann level, which matches up with our target above (with an initial target at 912).
UPDATE: It pulled back a little more than expected (905.25, close!) and after hitting 914.00 (1-2 ticks from target), price fell off 8 points. There was also a 5 point reaction at the 912 area on the way up.

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