30.52% is the change from 521 to 680
Calculation steps:
[( 680 - 521 ) ÷ 521] x 100 = 30.52%
Formula
Percentage change = [(680 - 521) / 521] x 100
Subtract the new number by the original number
680 - 521 = 159
159 ÷ 521 = 0.30518234165067176
0.30518234165067176 x 100 = 30.52%