-0.8% is the change from 870 to 863
Calculation steps:
[( 863 - 870 ) ÷ 870] x 100 = -0.8%
Formula
Percentage change = [(863 - 870) / 870] x 100
Subtract the new number by the original number
863 - 870 = -7
-7 ÷ 870 = -0.008045977011494253
-0.008045977011494253 x 100 = -0.8%