-39.62% is the change from 424 to 256
Calculation steps:
[( 256 - 424 ) ÷ 424] x 100 = -39.62%
Formula
Percentage change = [(256 - 424) / 424] x 100
Subtract the new number by the original number
256 - 424 = -168
-168 ÷ 424 = -0.39622641509433965
-0.39622641509433965 x 100 = -39.62%