-81.45% is the change from 539 to 100
Calculation steps:
[( 100 - 539 ) ÷ 539] x 100 = -81.45%
Formula
Percentage change = [(100 - 539) / 539] x 100
Subtract the new number by the original number
100 - 539 = -439
-439 ÷ 539 = -0.8144712430426716
-0.8144712430426716 x 100 = -81.45%