-39.45% is the change from 256 to 155
Calculation steps:
[( 155 - 256 ) ÷ 256] x 100 = -39.45%
Formula
Percentage change = [(155 - 256) / 256] x 100
Subtract the new number by the original number
155 - 256 = -101
-101 ÷ 256 = -0.39453125
-0.39453125 x 100 = -39.45%