19.87% is the change from 639 to 766
Calculation steps:
[( 766 - 639 ) ÷ 639] x 100 = 19.87%
Formula
Percentage change = [(766 - 639) / 639] x 100
Subtract the new number by the original number
766 - 639 = 127
127 ÷ 639 = 0.19874804381846636
0.19874804381846636 x 100 = 19.87%