0.78% is the change from 639 to 644
Calculation steps:
[( 644 - 639 ) ÷ 639] x 100 = 0.78%
Formula
Percentage change = [(644 - 639) / 639] x 100
Subtract the new number by the original number
644 - 639 = 5
5 ÷ 639 = 0.00782472613458529
0.00782472613458529 x 100 = 0.78%