-93.33% is the change from 255 to 17
Calculation steps:
[( 17 - 255 ) ÷ 255] x 100 = -93.33%
Formula
Percentage change = [(17 - 255) / 255] x 100
Subtract the new number by the original number
17 - 255 = -238
-238 ÷ 255 = -0.9333333333333333
-0.9333333333333333 x 100 = -93.33%