-42.07% is the change from 870 to 504
Calculation steps:
[( 504 - 870 ) ÷ 870] x 100 = -42.07%
Formula
Percentage change = [(504 - 870) / 870] x 100
Subtract the new number by the original number
504 - 870 = -366
-366 ÷ 870 = -0.4206896551724138
-0.4206896551724138 x 100 = -42.07%