3087.5% is the change from 8 to 255
Calculation steps:
[( 255 - 8 ) ÷ 8] x 100 = 3087.5%
Formula
Percentage change = [(255 - 8) / 8] x 100
Subtract the new number by the original number
255 - 8 = 247
247 ÷ 8 = 30.875
30.875 x 100 = 3087.5%
Example