[Lia Yin]

Hi nguyenchihieu82vn,
You can start with the task in a different way.
use data,
keep ccode
duplicates drop ccode
expand 11
bysort ccode:gen year=1999+_n
sort ccode year
merge ccode year using data,
This should work for the data you show.
Best

Worked like a charm. Thanks!

[Anton Lang]

Dear Nick and Clyde,

in Stata 16.0 I have panel data of political parties in different countries over different elections. Sometimes there are multiple cabinets formed after a single election – in those cases, there are observations for each start_date for each party, but all with the same eletion_date. Sometimes a party does not gain any seats and thus has no observations for the following election, sometimes it gains again in a later election and has an observation again.

I want to generate a variable stating if a party was in office at least for one year in a legislative term, what I aim to do by calculating the time from the current start_date until the next start_date and then using the “total()” command to sum the time by election_date. For this I first need to fill in observations for each party and start_date. In the end I will collapse the data only containing one observation for each party and election_date in that the party gained seats, which I will then “xtset” as my panel and time variable for analysis.

My question: How can I fill in observations for all start_dates happening in a country for every party of that country?
Neither the tsfill or fillin commands allow the “by()” option and I have yet to find another way. Using those commands fills in every start_date of every country for every party.

Thank you!

* Example generated by -dataex-. To install: ssc install dataex
clear
input str14 country_name int(party_id election_date start_date)
"Netherlands" 300 -15157 -15089
"Netherlands" 405 -15157 -15089
"Netherlands" 300 -13694 -13619
"Netherlands" 405 -13694 -13619
"Netherlands" 300 -12602 -12568
"Netherlands" 405 -12602 -12568
"Netherlands" 300 -12602 -12352
"Netherlands" 405 -12602 -12352
"Netherlands" 300 -11139 -11101
"Netherlands" 405 -11139 -11101
"Netherlands" 300  -9746  -9716
"Netherlands" 405  -9746  -9716
"Netherlands" 300  -9746  -8920
"Netherlands" 405  -9746  -8920
"Netherlands" 300  -8255  -8226
"Netherlands" 405  -8255  -8226
"Netherlands" 300  -8255  -7465
"Netherlands" 405  -8255  -7465
"Netherlands" 300  -8255  -7449
"Netherlands" 405  -8255  -7449
end
format %tddd/nn/CCYY election_date
format %tddd/nn/CCYY start_date