-55.1% is the change from 686 to 308
Calculation steps:
[( 308 - 686 ) ÷ 686] x 100 = -55.1%
Formula
Percentage change = [(308 - 686) / 686] x 100
Subtract the new number by the original number
308 - 686 = -378
-378 ÷ 686 = -0.5510204081632653
-0.5510204081632653 x 100 = -55.1%