30.13% is the change from 312 to 406
Calculation steps:
[( 406 - 312 ) ÷ 312] x 100 = 30.13%
Formula
Percentage change = [(406 - 312) / 312] x 100
Subtract the new number by the original number
406 - 312 = 94
94 ÷ 312 = 0.30128205128205127
0.30128205128205127 x 100 = 30.13%