-2.33% is the change from 686 to 670
Calculation steps:
[( 670 - 686 ) ÷ 686] x 100 = -2.33%
Formula
Percentage change = [(670 - 686) / 686] x 100
Subtract the new number by the original number
670 - 686 = -16
-16 ÷ 686 = -0.023323615160349854
-0.023323615160349854 x 100 = -2.33%