-80.15% is the change from 821 to 163
Calculation steps:
[( 163 - 821 ) ÷ 821] x 100 = -80.15%
Formula
Percentage change = [(163 - 821) / 821] x 100
Subtract the new number by the original number
163 - 821 = -658
-658 ÷ 821 = -0.8014616321559074
-0.8014616321559074 x 100 = -80.15%