-22.91% is the change from 838 to 646
Calculation steps:
[( 646 - 838 ) ÷ 838] x 100 = -22.91%
Formula
Percentage change = [(646 - 838) / 838] x 100
Subtract the new number by the original number
646 - 838 = -192
-192 ÷ 838 = -0.22911694510739858
-0.22911694510739858 x 100 = -22.91%