-19.88% is the change from 855 to 685
Calculation steps:
[( 685 - 855 ) ÷ 855] x 100 = -19.88%
Formula
Percentage change = [(685 - 855) / 855] x 100
Subtract the new number by the original number
685 - 855 = -170
-170 ÷ 855 = -0.19883040935672514
-0.19883040935672514 x 100 = -19.88%