-45.49% is the change from 255 to 139
Calculation steps:
[( 139 - 255 ) ÷ 255] x 100 = -45.49%
Formula
Percentage change = [(139 - 255) / 255] x 100
Subtract the new number by the original number
139 - 255 = -116
-116 ÷ 255 = -0.4549019607843137
-0.4549019607843137 x 100 = -45.49%