-19.83% is the change from 686 to 550
Calculation steps:
[( 550 - 686 ) ÷ 686] x 100 = -19.83%
Formula
Percentage change = [(550 - 686) / 686] x 100
Subtract the new number by the original number
550 - 686 = -136
-136 ÷ 686 = -0.19825072886297376
-0.19825072886297376 x 100 = -19.83%