31.58% is the change from 399 to 525
Calculation steps:
[( 525 - 399 ) ÷ 399] x 100 = 31.58%
Formula
Percentage change = [(525 - 399) / 399] x 100
Subtract the new number by the original number
525 - 399 = 126
126 ÷ 399 = 0.3157894736842105
0.3157894736842105 x 100 = 31.58%