0.6% is the change from 666 to 670
Calculation steps:
[( 670 - 666 ) ÷ 666] x 100 = 0.6%
Formula
Percentage change = [(670 - 666) / 666] x 100
Subtract the new number by the original number
670 - 666 = 4
4 ÷ 666 = 0.006006006006006006
0.006006006006006006 x 100 = 0.6%