Convert monthly data to quarterly format

[Julie Jemutai]

I would like to convert my data from monthly to quarterly format in STATA. This will be the sum of the two variables, outpatient and admissions, into quarterly format. My data is in the attached format:

How do I go about it?

[Nick Cox]

Please note advice against photos in the FAQ and for giving us sample data in CODE listings.

You have year and month variables.

You can get quarterly dates from monthly dates by

gen qdate = qofd(dofm(ym(year, month)))
format %tq date

Then

 
collapse (sum) outpatient (sum) admissions, by(hospital qdate) 
​

[Emul Mulyana]

Thank you very much, this is very usefull for myself

[Eddie Brighton]

#2 One small typo there:
format %tq qdate

[Nick Cox]

Eddie Brighton Correct and thanks!