st: Fixing the value in egen command

[Choudry T Shehzad <C.T.Shehzad@rug.nl>]

Dear Statalisters:

I have a small question: In a panel data if I want to generate a
variable which takes the value equal to the mean of GDP I use the command

by country year, sort : egen float abxx = mean(GDP)

Now I want to make another variable that contains initial value of GDP
fixed (for all years) equal to e.g. value of GDP in year 1885
corresponding to each country. How can I modify the above command?

Thanks for help,

Tanveer
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