15.93% is the change from 521 to 604
Calculation steps:
[( 604 - 521 ) ÷ 521] x 100 = 15.93%
Formula
Percentage change = [(604 - 521) / 521] x 100
Subtract the new number by the original number
604 - 521 = 83
83 ÷ 521 = 0.15930902111324377
0.15930902111324377 x 100 = 15.93%