83.45% is the change from 139 to 255
Calculation steps:
[( 255 - 139 ) ÷ 139] x 100 = 83.45%
Formula
Percentage change = [(255 - 139) / 139] x 100
Subtract the new number by the original number
255 - 139 = 116
116 ÷ 139 = 0.8345323741007195
0.8345323741007195 x 100 = 83.45%