-96.77% is the change from 650 to 21
Calculation steps:
[( 21 - 650 ) ÷ 650] x 100 = -96.77%
Formula
Percentage change = [(21 - 650) / 650] x 100
Subtract the new number by the original number
21 - 650 = -629
-629 ÷ 650 = -0.9676923076923077
-0.9676923076923077 x 100 = -96.77%