-97.45% is the change from 823 to 21
Calculation steps:
[( 21 - 823 ) ÷ 823] x 100 = -97.45%
Formula
Percentage change = [(21 - 823) / 823] x 100
Subtract the new number by the original number
21 - 823 = -802
-802 ÷ 823 = -0.9744835965978129
-0.9744835965978129 x 100 = -97.45%