-37.16% is the change from 810 to 509
Calculation steps:
[( 509 - 810 ) ÷ 810] x 100 = -37.16%
Formula
Percentage change = [(509 - 810) / 810] x 100
Subtract the new number by the original number
509 - 810 = -301
-301 ÷ 810 = -0.37160493827160496
-0.37160493827160496 x 100 = -37.16%