23.22% is the change from 521 to 642
Calculation steps:
[( 642 - 521 ) ÷ 521] x 100 = 23.22%
Formula
Percentage change = [(642 - 521) / 521] x 100
Subtract the new number by the original number
642 - 521 = 121
121 ÷ 521 = 0.23224568138195778
0.23224568138195778 x 100 = 23.22%