-80.76% is the change from 821 to 158
Calculation steps:
[( 158 - 821 ) ÷ 821] x 100 = -80.76%
Formula
Percentage change = [(158 - 821) / 821] x 100
Subtract the new number by the original number
158 - 821 = -663
-663 ÷ 821 = -0.807551766138855
-0.807551766138855 x 100 = -80.76%