It is not clear whether Naceur has one variable with chunks belonging 
to each country ("long" format, in which Uli's solution with by 
country, sort: egen xbar = mean(xi) would work well) or six variables 
named x_1 - x_6 ("wide" format). Assuming the latter:
forval i=1/6 {
	summ x_`i'. meanonly
	qui replace x_`i' = x`i' - r(mean)
	}
If a new set of variables are desired, the second line in the loop 
could be
	qui gen xc_`i' = x_`i' - r(mean)
Kit Baum, Boston College Economics
http://ideas.repec.org/e/pba1.html
On Dec 7, 2004, at 2:33 AM, Naceur wrote:
First, I have a variable x_i for each six country (i = 1,...,6) and I 
want to calculate the difference x_i - xbar_i. Or the xbar_i  is the 
mean of the variable of x_i for each country. Did you have an idea 
about the command that I should do?
Kit Baum, Boston College Economics
http://ideas.repec.org/e/pba1.html
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