-32.55% is the change from 255 to 172
Calculation steps:
[( 172 - 255 ) ÷ 255] x 100 = -32.55%
Formula
Percentage change = [(172 - 255) / 255] x 100
Subtract the new number by the original number
172 - 255 = -83
-83 ÷ 255 = -0.3254901960784314
-0.3254901960784314 x 100 = -32.55%