-24.36% is the change from 821 to 621
Calculation steps:
[( 621 - 821 ) ÷ 821] x 100 = -24.36%
Formula
Percentage change = [(621 - 821) / 821] x 100
Subtract the new number by the original number
621 - 821 = -200
-200 ÷ 821 = -0.243605359317905
-0.243605359317905 x 100 = -24.36%