3.36% is the change from 625 to 646
Calculation steps:
[( 646 - 625 ) ÷ 625] x 100 = 3.36%
Formula
Percentage change = [(646 - 625) / 625] x 100
Subtract the new number by the original number
646 - 625 = 21
21 ÷ 625 = 0.0336
0.0336 x 100 = 3.36%
Example