-0.97% is the change from 621 to 615
Calculation steps:
[( 615 - 621 ) ÷ 621] x 100 = -0.97%
Formula
Percentage change = [(615 - 621) / 621] x 100
Subtract the new number by the original number
615 - 621 = -6
-6 ÷ 621 = -0.00966183574879227
-0.00966183574879227 x 100 = -0.97%