-41.73% is the change from 671 to 391
Calculation steps:
[( 391 - 671 ) ÷ 671] x 100 = -41.73%
Formula
Percentage change = [(391 - 671) / 671] x 100
Subtract the new number by the original number
391 - 671 = -280
-280 ÷ 671 = -0.4172876304023845
-0.4172876304023845 x 100 = -41.73%