-40.8% is the change from 821 to 486
Calculation steps:
[( 486 - 821 ) ÷ 821] x 100 = -40.8%
Formula
Percentage change = [(486 - 821) / 821] x 100
Subtract the new number by the original number
486 - 821 = -335
-335 ÷ 821 = -0.40803897685749085
-0.40803897685749085 x 100 = -40.8%