-36.54% is the change from 509 to 323
Calculation steps:
[( 323 - 509 ) ÷ 509] x 100 = -36.54%
Formula
Percentage change = [(323 - 509) / 509] x 100
Subtract the new number by the original number
323 - 509 = -186
-186 ÷ 509 = -0.3654223968565815
-0.3654223968565815 x 100 = -36.54%