-69.26% is the change from 836 to 257
Calculation steps:
[( 257 - 836 ) ÷ 836] x 100 = -69.26%
Formula
Percentage change = [(257 - 836) / 836] x 100
Subtract the new number by the original number
257 - 836 = -579
-579 ÷ 836 = -0.6925837320574163
-0.6925837320574163 x 100 = -69.26%