-18.03% is the change from 671 to 550
Calculation steps:
[( 550 - 671 ) ÷ 671] x 100 = -18.03%
Formula
Percentage change = [(550 - 671) / 671] x 100
Subtract the new number by the original number
550 - 671 = -121
-121 ÷ 671 = -0.18032786885245902
-0.18032786885245902 x 100 = -18.03%