-21.84% is the change from 499 to 390
Calculation steps:
[( 390 - 499 ) ÷ 499] x 100 = -21.84%
Formula
Percentage change = [(390 - 499) / 499] x 100
Subtract the new number by the original number
390 - 499 = -109
-109 ÷ 499 = -0.218436873747495
-0.218436873747495 x 100 = -21.84%