-86.21% is the change from 580 to 80
Calculation steps:
[( 80 - 580 ) ÷ 580] x 100 = -86.21%
Formula
Percentage change = [(80 - 580) / 580] x 100
Subtract the new number by the original number
80 - 580 = -500
-500 ÷ 580 = -0.8620689655172413
-0.8620689655172413 x 100 = -86.21%