-83.9% is the change from 528 to 85
Calculation steps:
[( 85 - 528 ) ÷ 528] x 100 = -83.9%
Formula
Percentage change = [(85 - 528) / 528] x 100
Subtract the new number by the original number
85 - 528 = -443
-443 ÷ 528 = -0.8390151515151515
-0.8390151515151515 x 100 = -83.9%