-79.69% is the change from 842 to 171
Calculation steps:
[( 171 - 842 ) ÷ 842] x 100 = -79.69%
Formula
Percentage change = [(171 - 842) / 842] x 100
Subtract the new number by the original number
171 - 842 = -671
-671 ÷ 842 = -0.7969121140142518
-0.7969121140142518 x 100 = -79.69%