42.06% is the change from 321 to 456
Calculation steps:
[( 456 - 321 ) ÷ 321] x 100 = 42.06%
Formula
Percentage change = [(456 - 321) / 321] x 100
Subtract the new number by the original number
456 - 321 = 135
135 ÷ 321 = 0.4205607476635514
0.4205607476635514 x 100 = 42.06%