-68.74% is the change from 819 to 256
Calculation steps:
[( 256 - 819 ) ÷ 819] x 100 = -68.74%
Formula
Percentage change = [(256 - 819) / 819] x 100
Subtract the new number by the original number
256 - 819 = -563
-563 ÷ 819 = -0.6874236874236874
-0.6874236874236874 x 100 = -68.74%