Filling in dates for particular period

[Sein Kim]

Hello, all

I'm trying to fill in month and year for a particular period, and tried several things...
First, I made my "mon" variable ascending from Jan 2013.
Each individual has 80 months from 2013.Jan to 2019.August. What I want to do is to copy 80 months (from 2013m1 to 2019m8) to every individual in the dataset. Could you help me how I can do this?

caseid i syear sm end year em met mon
545 30 2 80 2013 1 1428 2018 12 0 2013m1
545 30 2 79 2013 1 1428 2018 12 0 2013m2
545 30 2 78 2013 1 1428 2018 12 0 2013m3
545 30 2 77 2013 1 1428 2018 12 0 2013m4
545 30 2 76 2013 1 1428 2018 12 0 2013m5
545 30 2 75 2013 1 1428 2018 12 0 2013m6
545 30 2 74 2013 1 1428 2018 12 0 2013m7
545 30 2 73 2013 1 1428 2018 12 0 2013m8
545 30 2 72 2013 1 1428 2018 12 0 2013m9
545 30 2 71 2013 1 1428 2018 12 0 2013m10
\\\\\
545 30 2 1 2013 1 1428 2018 12 0 2019m8

545 29 2 80 2013 1 1428 2018 12 0 2013m1
545 29 2 79 2013 1 1428 2018 12 0 2013m2
545 29 2 78 2013 1 1428 2018 12 0 2013m3

Thank you!

[Nick Cox]

Sounds like some variation on

bysort caseid : gen wanted = ym(2012, 12) + _n 
format wanted %tm