-35.32% is the change from 821 to 531
Calculation steps:
[( 531 - 821 ) ÷ 821] x 100 = -35.32%
Formula
Percentage change = [(531 - 821) / 821] x 100
Subtract the new number by the original number
531 - 821 = -290
-290 ÷ 821 = -0.35322777101096225
-0.35322777101096225 x 100 = -35.32%