-98.64% is the change from 662 to 9
Calculation steps:
[( 9 - 662 ) ÷ 662] x 100 = -98.64%
Formula
Percentage change = [(9 - 662) / 662] x 100
Subtract the new number by the original number
9 - 662 = -653
-653 ÷ 662 = -0.986404833836858
-0.986404833836858 x 100 = -98.64%