-29.95% is the change from 878 to 615
Calculation steps:
[( 615 - 878 ) ÷ 878] x 100 = -29.95%
Formula
Percentage change = [(615 - 878) / 878] x 100
Subtract the new number by the original number
615 - 878 = -263
-263 ÷ 878 = -0.29954441913439633
-0.29954441913439633 x 100 = -29.95%