-40.6% is the change from 431 to 256
Calculation steps:
[( 256 - 431 ) ÷ 431] x 100 = -40.6%
Formula
Percentage change = [(256 - 431) / 431] x 100
Subtract the new number by the original number
256 - 431 = -175
-175 ÷ 431 = -0.4060324825986079
-0.4060324825986079 x 100 = -40.6%