1.15% is the change from 870 to 880
Calculation steps:
[( 880 - 870 ) ÷ 870] x 100 = 1.15%
Formula
Percentage change = [(880 - 870) / 870] x 100
Subtract the new number by the original number
880 - 870 = 10
10 ÷ 870 = 0.011494252873563218
0.011494252873563218 x 100 = 1.15%