-50.36% is the change from 280 to 139
Calculation steps:
[( 139 - 280 ) ÷ 280] x 100 = -50.36%
Formula
Percentage change = [(139 - 280) / 280] x 100
Subtract the new number by the original number
139 - 280 = -141
-141 ÷ 280 = -0.5035714285714286
-0.5035714285714286 x 100 = -50.36%