-99.03% is the change from 821 to 8
Calculation steps:
[( 8 - 821 ) ÷ 821] x 100 = -99.03%
Formula
Percentage change = [(8 - 821) / 821] x 100
Subtract the new number by the original number
8 - 821 = -813
-813 ÷ 821 = -0.9902557856272838
-0.9902557856272838 x 100 = -99.03%