0.1% is the change from 999 to 1000
Calculation steps:
[( 1000 - 999 ) ÷ 999] x 100 = 0.1%
Formula
Percentage change = [(1000 - 999) / 999] x 100
Subtract the new number by the original number
1000 - 999 = 1
1 ÷ 999 = 0.001001001001001001
0.001001001001001001 x 100 = 0.1%