-6.56% is the change from 686 to 641
Calculation steps:
[( 641 - 686 ) ÷ 686] x 100 = -6.56%
Formula
Percentage change = [(641 - 686) / 686] x 100
Subtract the new number by the original number
641 - 686 = -45
-45 ÷ 686 = -0.06559766763848396
-0.06559766763848396 x 100 = -6.56%