Monthly last observation in a temporal series

[Fabio Colares]

Hi, I have a temporal series with the follow variables: idcompany, lastprice and date (dd/mm/yyyy). I have set variable date as temporal series data and idcompany my Panel Id Variable. So, I need generate another dataset with only the last price in each month of each company. How can I do it?

[Nick Cox]

gen mdate = mofd(date)
bysort idcompany mdate (date) : keep if _n = _N

[Clyde Schechter]

N.B. It is not clear in #1 whether the currently existing date variable is a string formatted dd/mm/yyyy or a Stata internal format date variable with display format %tdDD/NN/CCYY. If the former, you will first need to convert it to the latter, using the -daily()- function, before you can use Nick's code.

[Nick Cox]

To me #1 implied some use of tsset or xtset, not possible unless the date variable is numeric.

[Clyde Schechter]

Good point, Nick.

[Fabio Colares]

Hi, I solved my issue with commands below using the same dataset. Stata is totally new for me.

gen long first_of_next_month = dofm(mofd(mypricedate)+1

keep if mypricedate + 1 == first_of_next-Month

Thanks a lot!

[Clyde Schechter]

Thanks for showing your solution. I think you left off a closing ) character in your -gen- command. Shouldn't it be
[code]
gen long first_of_next_month = dofm(mofd(mypricedate))+1

[Fabio Colares]

Oh, yes, of course, Thanks!