-69.38% is the change from 836 to 256
Calculation steps:
[( 256 - 836 ) ÷ 836] x 100 = -69.38%
Formula
Percentage change = [(256 - 836) / 836] x 100
Subtract the new number by the original number
256 - 836 = -580
-580 ÷ 836 = -0.69377990430622
-0.69377990430622 x 100 = -69.38%