-1.28% is the change from 623 to 615
Calculation steps:
[( 615 - 623 ) ÷ 623] x 100 = -1.28%
Formula
Percentage change = [(615 - 623) / 623] x 100
Subtract the new number by the original number
615 - 623 = -8
-8 ÷ 623 = -0.012841091492776886
-0.012841091492776886 x 100 = -1.28%