-69.14% is the change from 256 to 79
Calculation steps:
[( 79 - 256 ) ÷ 256] x 100 = -69.14%
Formula
Percentage change = [(79 - 256) / 256] x 100
Subtract the new number by the original number
79 - 256 = -177
-177 ÷ 256 = -0.69140625
-0.69140625 x 100 = -69.14%