merging datasets

[Ivano Scandurra]

Hi,
I need help to merge information into an existing dataset, which has a wide format. In the rows I have got each region with the same identifier
Exemple of the dataset
Demo Reg year
139775 AT11 1990
752424 AT12 1990
808630 AT13 1990
281917 AT21 1990
607186 AT22 1990
670153 AT31 1990
246020 AT32 1990
318816 AT33 1990
164982 AT34 1990
I would like to merge information from different tables in Excel format such as:

Reg	1990	1991	1992
AT11	22.5	18.4	17.3
AT12	19.2	17.8	17.2
AT13	16.6	8.6	9.3
AT21	36.5	23.5	23.9
AT33		13.1	12.4
AT34		21.4	19.4

I understand that I need to merge by identifier and year, but I would need to copy the year for each datapoint and copy paste the year to have the data into a single column. Is there any option in stata to do it automatically?
Thanks for your help.

[Josh Clothiaux]

You could merge it piece-wise by saving different .dta files for each year (with a new variable "year" equal to the year (i.e. 1990) for your using data).

[Jannic Cutura]

Yes Stata can do that for you. You are looking for reshappe. First reshape the excel data and then merge it using the merge command.

help reshape
help merge

provide various examples.