Dear all

I am using the South African National Income Dynamics Survey (NIDs) and have successively created a panel dataset across all 5 waves.
I am looking to create a variable for 'household income per capita' quintiles that is categorized according to 5 percentiles so that you have the "bottom 20th percentile", "20th - 40th percentile" etc.
It should be easy enough to make since i have a derived variable for 'household income' and a variable for the number of people in a household.

I have tried using the following command:


sort w`i'_hhincome

xtile w`i'_inc = w`i'_hhincome, nq(5)
tab w`i'_inc

}

forvalues i = 1(1)5 {


// income per capita

sort w`i'_hhincome
cap gen w`i'_hh_capita = w`i'_hhincome/w`i'_hhsizer
cap xtile w`i'_inc_capita = w`i'_hh_capita, nq(5)
tab w`i'_inc_capita


}

But it ends up giving me the following result:

5 quantiles |
of |
w5_hh_capit |
a | Freq. Percent Cum.
------------+-----------------------------------
1 | 8,194 20.01 20.01
2 | 8,186 19.99 40.01
3 | 8,191 20.01 60.01
4 | 8,185 19.99 80.00
5 | 8,188 20.00 100.00
------------+-----------------------------------
Total | 40,944 100.00


Can anyone help me understand whether this is the correct way to generate such a variable as it seems odd that the percentages are so similar?

Kind regards
Sophie Gebers