-81.18% is the change from 255 to 48
Calculation steps:
[( 48 - 255 ) ÷ 255] x 100 = -81.18%
Formula
Percentage change = [(48 - 255) / 255] x 100
Subtract the new number by the original number
48 - 255 = -207
-207 ÷ 255 = -0.8117647058823529
-0.8117647058823529 x 100 = -81.18%