-1.91% is the change from 679 to 666
Calculation steps:
[( 666 - 679 ) ÷ 679] x 100 = -1.91%
Formula
Percentage change = [(666 - 679) / 679] x 100
Subtract the new number by the original number
666 - 679 = -13
-13 ÷ 679 = -0.01914580265095729
-0.01914580265095729 x 100 = -1.91%