the data is monthly level data.

Coding of the time index variables are as follows:

Year: 2005-2018
Month: 1-12
Year_Month: 1-168
Year_sequence: 1-14
Month_sequence: 1-12

I expect that each area has specific trend. How to control for area specific trend (linear)?


Code:
xtset area_id Year_Month
            xtreg Y X  ??????, fe r



Thanks!!!!