38.03% is the change from 305 to 421
Calculation steps:
[( 421 - 305 ) ÷ 305] x 100 = 38.03%
Formula
Percentage change = [(421 - 305) / 305] x 100
Subtract the new number by the original number
421 - 305 = 116
116 ÷ 305 = 0.380327868852459
0.380327868852459 x 100 = 38.03%