-21.24% is the change from 871 to 686
Calculation steps:
[( 686 - 871 ) ÷ 871] x 100 = -21.24%
Formula
Percentage change = [(686 - 871) / 871] x 100
Subtract the new number by the original number
686 - 871 = -185
-185 ÷ 871 = -0.21239954075774972
-0.21239954075774972 x 100 = -21.24%