-19.37% is the change from 821 to 662
Calculation steps:
[( 662 - 821 ) ÷ 821] x 100 = -19.37%
Formula
Percentage change = [(662 - 821) / 821] x 100
Subtract the new number by the original number
662 - 821 = -159
-159 ÷ 821 = -0.19366626065773446
-0.19366626065773446 x 100 = -19.37%