-15.83% is the change from 499 to 420
Calculation steps:
[( 420 - 499 ) ÷ 499] x 100 = -15.83%
Formula
Percentage change = [(420 - 499) / 499] x 100
Subtract the new number by the original number
420 - 499 = -79
-79 ÷ 499 = -0.15831663326653306
-0.15831663326653306 x 100 = -15.83%