-0.12% is the change from 822 to 821
Calculation steps:
[( 821 - 822 ) ÷ 822] x 100 = -0.12%
Formula
Percentage change = [(821 - 822) / 822] x 100
Subtract the new number by the original number
821 - 822 = -1
-1 ÷ 822 = -0.0012165450121654502
-0.0012165450121654502 x 100 = -0.12%