-5.86% is the change from 871 to 820
Calculation steps:
[( 820 - 871 ) ÷ 871] x 100 = -5.86%
Formula
Percentage change = [(820 - 871) / 871] x 100
Subtract the new number by the original number
820 - 871 = -51
-51 ÷ 871 = -0.05855338691159587
-0.05855338691159587 x 100 = -5.86%