34.94% is the change from 312 to 421
Calculation steps:
[( 421 - 312 ) ÷ 312] x 100 = 34.94%
Formula
Percentage change = [(421 - 312) / 312] x 100
Subtract the new number by the original number
421 - 312 = 109
109 ÷ 312 = 0.34935897435897434
0.34935897435897434 x 100 = 34.94%