-83.8% is the change from 531 to 86
Calculation steps:
[( 86 - 531 ) ÷ 531] x 100 = -83.8%
Formula
Percentage change = [(86 - 531) / 531] x 100
Subtract the new number by the original number
86 - 531 = -445
-445 ÷ 531 = -0.8380414312617702
-0.8380414312617702 x 100 = -83.8%