-8.35% is the change from 671 to 615
Calculation steps:
[( 615 - 671 ) ÷ 671] x 100 = -8.35%
Formula
Percentage change = [(615 - 671) / 671] x 100
Subtract the new number by the original number
615 - 671 = -56
-56 ÷ 671 = -0.08345752608047691
-0.08345752608047691 x 100 = -8.35%