-5.69% is the change from 686 to 647
Calculation steps:
[( 647 - 686 ) ÷ 686] x 100 = -5.69%
Formula
Percentage change = [(647 - 686) / 686] x 100
Subtract the new number by the original number
647 - 686 = -39
-39 ÷ 686 = -0.056851311953352766
-0.056851311953352766 x 100 = -5.69%