1.09% is the change from 640 to 647
Calculation steps:
[( 647 - 640 ) ÷ 640] x 100 = 1.09%
Formula
Percentage change = [(647 - 640) / 640] x 100
Subtract the new number by the original number
647 - 640 = 7
7 ÷ 640 = 0.0109375
0.0109375 x 100 = 1.09%
Example