-53.21% is the change from 686 to 321
Calculation steps:
[( 321 - 686 ) ÷ 686] x 100 = -53.21%
Formula
Percentage change = [(321 - 686) / 686] x 100
Subtract the new number by the original number
321 - 686 = -365
-365 ÷ 686 = -0.532069970845481
-0.532069970845481 x 100 = -53.21%