-96.79% is the change from 280 to 9
Calculation steps:
[( 9 - 280 ) ÷ 280] x 100 = -96.79%
Formula
Percentage change = [(9 - 280) / 280] x 100
Subtract the new number by the original number
9 - 280 = -271
-271 ÷ 280 = -0.9678571428571429
-0.9678571428571429 x 100 = -96.79%