-98.89% is the change from 809 to 9
Calculation steps:
[( 9 - 809 ) ÷ 809] x 100 = -98.89%
Formula
Percentage change = [(9 - 809) / 809] x 100
Subtract the new number by the original number
9 - 809 = -800
-800 ÷ 809 = -0.9888751545117429
-0.9888751545117429 x 100 = -98.89%