-2.06% is the change from 680 to 666
Calculation steps:
[( 666 - 680 ) ÷ 680] x 100 = -2.06%
Formula
Percentage change = [(666 - 680) / 680] x 100
Subtract the new number by the original number
666 - 680 = -14
-14 ÷ 680 = -0.020588235294117647
-0.020588235294117647 x 100 = -2.06%