-17.09% is the change from 509 to 422
Calculation steps:
[( 422 - 509 ) ÷ 509] x 100 = -17.09%
Formula
Percentage change = [(422 - 509) / 509] x 100
Subtract the new number by the original number
422 - 509 = -87
-87 ÷ 509 = -0.17092337917485265
-0.17092337917485265 x 100 = -17.09%