-80.58% is the change from 855 to 166
Calculation steps:
[( 166 - 855 ) ÷ 855] x 100 = -80.58%
Formula
Percentage change = [(166 - 855) / 855] x 100
Subtract the new number by the original number
166 - 855 = -689
-689 ÷ 855 = -0.8058479532163743
-0.8058479532163743 x 100 = -80.58%