-0.3% is the change from 999 to 996
Calculation steps:
[( 996 - 999 ) ÷ 999] x 100 = -0.3%
Formula
Percentage change = [(996 - 999) / 999] x 100
Subtract the new number by the original number
996 - 999 = -3
-3 ÷ 999 = -0.003003003003003003
-0.003003003003003003 x 100 = -0.3%