-83.05% is the change from 531 to 90
Calculation steps:
[( 90 - 531 ) ÷ 531] x 100 = -83.05%
Formula
Percentage change = [(90 - 531) / 531] x 100
Subtract the new number by the original number
90 - 531 = -441
-441 ÷ 531 = -0.8305084745762712
-0.8305084745762712 x 100 = -83.05%