-81.42% is the change from 646 to 120
Calculation steps:
[( 120 - 646 ) ÷ 646] x 100 = -81.42%
Formula
Percentage change = [(120 - 646) / 646] x 100
Subtract the new number by the original number
120 - 646 = -526
-526 ÷ 646 = -0.8142414860681114
-0.8142414860681114 x 100 = -81.42%