29.55% is the change from 308 to 399
Calculation steps:
[( 399 - 308 ) ÷ 308] x 100 = 29.55%
Formula
Percentage change = [(399 - 308) / 308] x 100
Subtract the new number by the original number
399 - 308 = 91
91 ÷ 308 = 0.29545454545454547
0.29545454545454547 x 100 = 29.55%