-47.06% is the change from 255 to 135
Calculation steps:
[( 135 - 255 ) ÷ 255] x 100 = -47.06%
Formula
Percentage change = [(135 - 255) / 255] x 100
Subtract the new number by the original number
135 - 255 = -120
-120 ÷ 255 = -0.47058823529411764
-0.47058823529411764 x 100 = -47.06%