3.16% is the change from 665 to 686
Calculation steps:
[( 686 - 665 ) ÷ 665] x 100 = 3.16%
Formula
Percentage change = [(686 - 665) / 665] x 100
Subtract the new number by the original number
686 - 665 = 21
21 ÷ 665 = 0.031578947368421054
0.031578947368421054 x 100 = 3.16%