-12.01% is the change from 999 to 879
Calculation steps:
[( 879 - 999 ) ÷ 999] x 100 = -12.01%
Formula
Percentage change = [(879 - 999) / 999] x 100
Subtract the new number by the original number
879 - 999 = -120
-120 ÷ 999 = -0.12012012012012012
-0.12012012012012012 x 100 = -12.01%