3.93% is the change from 509 to 529
Calculation steps:
[( 529 - 509 ) ÷ 509] x 100 = 3.93%
Formula
Percentage change = [(529 - 509) / 509] x 100
Subtract the new number by the original number
529 - 509 = 20
20 ÷ 509 = 0.03929273084479371
0.03929273084479371 x 100 = 3.93%