How to know the average time a household spent in my sample?

[Michael Duarte Goncalves]

Hi everyone,

I have a quick question to ask you. I have a dataset about contract starting dates, and contract ending dates about household electricity consumption in Spain. My aim is:

• I would like to know how much time spent, on average, households in my sample, please.

Here is a small -dataex- for my first ID:

* Example generated by -dataex-. For more info, type help dataex
clear
input long id double(date_contract_start date_contract_end)
1001 18887 21700
1001 21701 22431
1001 22432 22645
1001 22646 22676
1001 22677 22735
1001 22736 23010
1001 23011 23069
1001 23070     .

Could you give me some insights on how to do that?
Thank you very much in advance.
Best,

Michael

Edit: Sometimes, the date_contract_end is missing, meaning that this household's contract is not terminated.

[George Ford]

g contract_time = date_contract_end - date_contract_start
egen timeinsample = sum(contract_time), by(id)

I'm not sure whether HH drop in an out. If not, then this would work too.

egen mark_start = min(date_contract_start), by(id)
egen mark_end = max(date_contract_end), by(id)
bys id: g timeinsample = mark_end - mark_start

[Michael Duarte Goncalves]

Hi George Ford:

Thank you so much for your help, and time! Yes, in fact, HH can drop in and out.
Have a lovely day.

Best,
Michael