-3.78% is the change from 529 to 509
Calculation steps:
[( 509 - 529 ) ÷ 529] x 100 = -3.78%
Formula
Percentage change = [(509 - 529) / 529] x 100
Subtract the new number by the original number
509 - 529 = -20
-20 ÷ 529 = -0.03780718336483932
-0.03780718336483932 x 100 = -3.78%