-86.07% is the change from 280 to 39
Calculation steps:
[( 39 - 280 ) ÷ 280] x 100 = -86.07%
Formula
Percentage change = [(39 - 280) / 280] x 100
Subtract the new number by the original number
39 - 280 = -241
-241 ÷ 280 = -0.8607142857142858
-0.8607142857142858 x 100 = -86.07%