-81.56% is the change from 640 to 118
Calculation steps:
[( 118 - 640 ) ÷ 640] x 100 = -81.56%
Formula
Percentage change = [(118 - 640) / 640] x 100
Subtract the new number by the original number
118 - 640 = -522
-522 ÷ 640 = -0.815625
-0.815625 x 100 = -81.56%