-8.79% is the change from 899 to 820
Calculation steps:
[( 820 - 899 ) ÷ 899] x 100 = -8.79%
Formula
Percentage change = [(820 - 899) / 899] x 100
Subtract the new number by the original number
820 - 899 = -79
-79 ÷ 899 = -0.0878754171301446
-0.0878754171301446 x 100 = -8.79%