Hi,
I have this little problem with the following code:

clear all
forval i=1/1{
use 201`i'-1.dta
merge m:m Semestre Carnet using 201`i+1'-1.dta
}

I work with two datas 2011-1.dta and 2012-1.dta, but the fourth line of my code dont work. Is there any way to do that in Stata?

Thanks in advance.