-83.99% is the change from 531 to 85
Calculation steps:
[( 85 - 531 ) ÷ 531] x 100 = -83.99%
Formula
Percentage change = [(85 - 531) / 531] x 100
Subtract the new number by the original number
85 - 531 = -446
-446 ÷ 531 = -0.839924670433145
-0.839924670433145 x 100 = -83.99%