38.51% is the change from 309 to 428
Calculation steps:
[( 428 - 309 ) ÷ 309] x 100 = 38.51%
Formula
Percentage change = [(428 - 309) / 309] x 100
Subtract the new number by the original number
428 - 309 = 119
119 ÷ 309 = 0.3851132686084142
0.3851132686084142 x 100 = 38.51%