-85.1% is the change from 255 to 38
Calculation steps:
[( 38 - 255 ) ÷ 255] x 100 = -85.1%
Formula
Percentage change = [(38 - 255) / 255] x 100
Subtract the new number by the original number
38 - 255 = -217
-217 ÷ 255 = -0.8509803921568627
-0.8509803921568627 x 100 = -85.1%