-19.41% is the change from 850 to 685
Calculation steps:
[( 685 - 850 ) ÷ 850] x 100 = -19.41%
Formula
Percentage change = [(685 - 850) / 850] x 100
Subtract the new number by the original number
685 - 850 = -165
-165 ÷ 850 = -0.19411764705882353
-0.19411764705882353 x 100 = -19.41%