-50.35% is the change from 999 to 496
Calculation steps:
[( 496 - 999 ) ÷ 999] x 100 = -50.35%
Formula
Percentage change = [(496 - 999) / 999] x 100
Subtract the new number by the original number
496 - 999 = -503
-503 ÷ 999 = -0.5035035035035035
-0.5035035035035035 x 100 = -50.35%