-34.12% is the change from 255 to 168
Calculation steps:
[( 168 - 255 ) ÷ 255] x 100 = -34.12%
Formula
Percentage change = [(168 - 255) / 255] x 100
Subtract the new number by the original number
168 - 255 = -87
-87 ÷ 255 = -0.3411764705882353
-0.3411764705882353 x 100 = -34.12%