30.82% is the change from 305 to 399
Calculation steps:
[( 399 - 305 ) ÷ 305] x 100 = 30.82%
Formula
Percentage change = [(399 - 305) / 305] x 100
Subtract the new number by the original number
399 - 305 = 94
94 ÷ 305 = 0.3081967213114754
0.3081967213114754 x 100 = 30.82%