-12.89% is the change from 256 to 223
Calculation steps:
[( 223 - 256 ) ÷ 256] x 100 = -12.89%
Formula
Percentage change = [(223 - 256) / 256] x 100
Subtract the new number by the original number
223 - 256 = -33
-33 ÷ 256 = -0.12890625
-0.12890625 x 100 = -12.89%