-6.43% is the change from 887 to 830
Calculation steps:
[( 830 - 887 ) ÷ 887] x 100 = -6.43%
Formula
Percentage change = [(830 - 887) / 887] x 100
Subtract the new number by the original number
830 - 887 = -57
-57 ÷ 887 = -0.06426155580608793
-0.06426155580608793 x 100 = -6.43%