31.48% is the change from 521 to 685
Calculation steps:
[( 685 - 521 ) ÷ 521] x 100 = 31.48%
Formula
Percentage change = [(685 - 521) / 521] x 100
Subtract the new number by the original number
685 - 521 = 164
164 ÷ 521 = 0.31477927063339733
0.31477927063339733 x 100 = 31.48%