-98.43% is the change from 255 to 4
Calculation steps:
[( 4 - 255 ) ÷ 255] x 100 = -98.43%
Formula
Percentage change = [(4 - 255) / 255] x 100
Subtract the new number by the original number
4 - 255 = -251
-251 ÷ 255 = -0.984313725490196
-0.984313725490196 x 100 = -98.43%