-13.75% is the change from 509 to 439
Calculation steps:
[( 439 - 509 ) ÷ 509] x 100 = -13.75%
Formula
Percentage change = [(439 - 509) / 509] x 100
Subtract the new number by the original number
439 - 509 = -70
-70 ÷ 509 = -0.137524557956778
-0.137524557956778 x 100 = -13.75%