20.58% is the change from 515 to 621
Calculation steps:
[( 621 - 515 ) ÷ 515] x 100 = 20.58%
Formula
Percentage change = [(621 - 515) / 515] x 100
Subtract the new number by the original number
621 - 515 = 106
106 ÷ 515 = 0.2058252427184466
0.2058252427184466 x 100 = 20.58%