-83.3% is the change from 539 to 90
Calculation steps:
[( 90 - 539 ) ÷ 539] x 100 = -83.3%
Formula
Percentage change = [(90 - 539) / 539] x 100
Subtract the new number by the original number
90 - 539 = -449
-449 ÷ 539 = -0.8330241187384044
-0.8330241187384044 x 100 = -83.3%