-25.79% is the change from 857 to 636
Calculation steps:
[( 636 - 857 ) ÷ 857] x 100 = -25.79%
Formula
Percentage change = [(636 - 857) / 857] x 100
Subtract the new number by the original number
636 - 857 = -221
-221 ÷ 857 = -0.25787631271878647
-0.25787631271878647 x 100 = -25.79%