-15.52% is the change from 638 to 539
Calculation steps:
[( 539 - 638 ) ÷ 638] x 100 = -15.52%
Formula
Percentage change = [(539 - 638) / 638] x 100
Subtract the new number by the original number
539 - 638 = -99
-99 ÷ 638 = -0.15517241379310345
-0.15517241379310345 x 100 = -15.52%