#Earnings $BIIB reports tonight. Below are details on earnings one-day moves over the last 12 quarters.

July 23, 2019 AC +5.18%
April 24, 2019 AC -4.46%
Feb. 6, 2019 AC +11.35%
Oct. 25, 2018 AC +3.42%
July 26, 2018 AC +5.71%
April 25, 2018 AC +24.44% Biggest UP
Feb. 6, 2018 AC -10.55%
Oct. 24, 2017 AC -14.58% Biggest DOWN
July 25, 2017 AC -2.30%
April 25, 2017 AC +2.38%
Feb. 2, 2017 AC -4.54%
Oct. 25, 2016 AC -9.28%

Avg (+ or -) 8.18%
Bias 0.56%, slight positive bias on earnings.

With stock at 850.00 the data suggests these ranges:
Based on current IV (expected move into Friday per TOS): 792.17 to 907.83
Based on AVERAGE one-day move over last 12 quarters: 780.45 to 919.55
Based on MAXIMUM one-day move over last 12 Q’s (24.4%): 642.26 to 1,057.74
Based on DOWN max only (-14.6%): 726.07

Open to requests for other symbols.