3.22% is the change from 622 to 642
Calculation steps:
[( 642 - 622 ) ÷ 622] x 100 = 3.22%
Formula
Percentage change = [(642 - 622) / 622] x 100
Subtract the new number by the original number
642 - 622 = 20
20 ÷ 622 = 0.03215434083601286
0.03215434083601286 x 100 = 3.22%