-52.3% is the change from 673 to 321
Calculation steps:
[( 321 - 673 ) ÷ 673] x 100 = -52.3%
Formula
Percentage change = [(321 - 673) / 673] x 100
Subtract the new number by the original number
321 - 673 = -352
-352 ÷ 673 = -0.5230312035661219
-0.5230312035661219 x 100 = -52.3%