-2.06% is the change from 873 to 855
Calculation steps:
[( 855 - 873 ) ÷ 873] x 100 = -2.06%
Formula
Percentage change = [(855 - 873) / 873] x 100
Subtract the new number by the original number
855 - 873 = -18
-18 ÷ 873 = -0.020618556701030927
-0.020618556701030927 x 100 = -2.06%