9.9% is the change from 606 to 666
Calculation steps:
[( 666 - 606 ) ÷ 606] x 100 = 9.9%
Formula
Percentage change = [(666 - 606) / 606] x 100
Subtract the new number by the original number
666 - 606 = 60
60 ÷ 606 = 0.09900990099009901
0.09900990099009901 x 100 = 9.9%