More information if you want to update de OP
MAU's of all Blizzard
2016
Q1: 26M
Q2: 33M (Overwatch Launch)
Q3: 42M (Legion Launch)
Q4: 36M
2017
Q1: 41M
Q2: 46M (Peak of Overwatch & Hearthstone)
Q3: 42M
Q4: 40M
2018
Q1: 38M
Q2: 37M
Q3: 37M (BfA Launch)
Q4: 35M
2019
Q1: 32M
Q2: 32M
Q3: 33M