-83.68% is the change from 999 to 163
Calculation steps:
[( 163 - 999 ) ÷ 999] x 100 = -83.68%
Formula
Percentage change = [(163 - 999) / 999] x 100
Subtract the new number by the original number
163 - 999 = -836
-836 ÷ 999 = -0.8368368368368369
-0.8368368368368369 x 100 = -83.68%