-22.35% is the change from 671 to 521
Calculation steps:
[( 521 - 671 ) ÷ 671] x 100 = -22.35%
Formula
Percentage change = [(521 - 671) / 671] x 100
Subtract the new number by the original number
521 - 671 = -150
-150 ÷ 671 = -0.22354694485842028
-0.22354694485842028 x 100 = -22.35%