-3.52% is the change from 256 to 247
Calculation steps:
[( 247 - 256 ) ÷ 256] x 100 = -3.52%
Formula
Percentage change = [(247 - 256) / 256] x 100
Subtract the new number by the original number
247 - 256 = -9
-9 ÷ 256 = -0.03515625
-0.03515625 x 100 = -3.52%