-79.78% is the change from 831 to 168
Calculation steps:
[( 168 - 831 ) ÷ 831] x 100 = -79.78%
Formula
Percentage change = [(168 - 831) / 831] x 100
Subtract the new number by the original number
168 - 831 = -663
-663 ÷ 831 = -0.7978339350180506
-0.7978339350180506 x 100 = -79.78%