personnel_1997.dta personnel_1998.dta ... personnel_2001.dta
------------------------------------------------
id year id year id year
101818 1997 101818 1998 101818 2001
102270 1997 102881 1998 103454 2001
102881 1997 103454 1998 104043 2001
103241 1997 103586 1998 104124 2001
103373 1997 103799 1998 104132 2001
103438 1997 104043 1998 104710 2001
103454 1997 104124 1998 104868 2001
103586 1997 104132 1998 105210 2001
103799 1997 104281 1998 105635 2001
103888 1997 104523 1998 105708 2001
...
Namely, there are attrition and/or entry of employees
during the panel period, though most of them survive
from start to end.
So, I thought using -merge- with each file matched by id
variable would be a better choice.
I'd appreciate additional advice if I am wrong.
It seems to me that you want to -append- all of these into a long format
file, where each record will be uniquely keyed by id -and- year. You can
then reshape wide, if you wish, to create variables where the same
individual shows up in the workforce (or not) year by year.
