-6.29% is the change from 875 to 820
Calculation steps:
[( 820 - 875 ) ÷ 875] x 100 = -6.29%
Formula
Percentage change = [(820 - 875) / 875] x 100
Subtract the new number by the original number
820 - 875 = -55
-55 ÷ 875 = -0.06285714285714286
-0.06285714285714286 x 100 = -6.29%