-19.65% is the change from 509 to 409
Calculation steps:
[( 409 - 509 ) ÷ 509] x 100 = -19.65%
Formula
Percentage change = [(409 - 509) / 509] x 100
Subtract the new number by the original number
409 - 509 = -100
-100 ÷ 509 = -0.19646365422396855
-0.19646365422396855 x 100 = -19.65%