4.54% is the change from 639 to 668
Calculation steps:
[( 668 - 639 ) ÷ 639] x 100 = 4.54%
Formula
Percentage change = [(668 - 639) / 639] x 100
Subtract the new number by the original number
668 - 639 = 29
29 ÷ 639 = 0.04538341158059468
0.04538341158059468 x 100 = 4.54%