Hi all,

hope everything is fine.
I have a question regarding this database:
Code:
* Example generated by -dataex-. To install: ssc install dataex
clear
input str6 quarter str26 Productlocal float panelsize
"2008Q4" "EXOMUC"   17
"2009Q1" "EXOMUC"   17
"2009Q2" "EXOMUC"   17
"2009Q3" "EXOMUC"   17
"2009Q4" "EXOMUC"   17
"2010Q1" "EXOMUC"   17
"2010Q2" "EXOMUC"   17
"2010Q3" "EXOMUC"   17
"2010Q4" "EXOMUC"   17
"2011Q1" "EXOMUC"   17
"2011Q2" "EXOMUC"   17
"2011Q3" "EXOMUC"   17
"2011Q4" "EXOMUC"   17
"2012Q1" "EXOMUC"   17
"2012Q2" "EXOMUC"   17
"2012Q4" "EXOMUC"   17
"2013Q1" "EXOMUC"   17
"2009Q4" "SOLMUCOL" 38
"2010Q1" "SOLMUCOL" 38
"2010Q2" "SOLMUCOL" 38
"2010Q3" "SOLMUCOL" 38
"2010Q4" "SOLMUCOL" 38
"2011Q1" "SOLMUCOL" 38
"2011Q2" "SOLMUCOL" 38
"2011Q3" "SOLMUCOL" 38
"2011Q4" "SOLMUCOL" 38
"2012Q1" "SOLMUCOL" 38
"2012Q2" "SOLMUCOL" 38
"2012Q3" "SOLMUCOL" 38
"2012Q4" "SOLMUCOL" 38
"2013Q1" "SOLMUCOL" 38
"2013Q2" "SOLMUCOL" 38
"2013Q3" "SOLMUCOL" 38
"2013Q4" "SOLMUCOL" 38
"2014Q1" "SOLMUCOL" 38
"2014Q2" "SOLMUCOL" 38
"2014Q3" "SOLMUCOL" 38
"2014Q4" "SOLMUCOL" 38
"2015Q1" "SOLMUCOL" 38
"2015Q2" "SOLMUCOL" 38
"2015Q3" "SOLMUCOL" 38
"2015Q4" "SOLMUCOL" 38
"2016Q1" "SOLMUCOL" 38
"2016Q2" "SOLMUCOL" 38
"2016Q3" "SOLMUCOL" 38
"2016Q4" "SOLMUCOL" 38
"2018Q2" "SOLMUCOL" 38
"2018Q3" "SOLMUCOL" 38
"2018Q4" "SOLMUCOL" 38
"2019Q1" "SOLMUCOL" 38
"2019Q2" "SOLMUCOL" 38
"2019Q3" "SOLMUCOL" 38
"2019Q4" "SOLMUCOL" 38
"2020Q1" "SOLMUCOL" 38
"2020Q2" "SOLMUCOL" 38
end
as you can see I have products observed for several quarters. Panelsize indicates the number of quarters in which a product is observed. In the above case, SOLMUCOL is observed for 38 quarters while EXOMUC for 17. Now, since I have to apply an algorithm that takes on only the same amount of quarters for each product, my idea is to basically take the number of quarters of the product that has fewer quarters. In this case EXOMUC. However, I would like to remove only the quarters of SOLMUCOL that are not present in EXOMUC. In other words, I would like to keep only the quarters of EEXOMUC also for SOLMUCOL. Since I have to repeat this operation for many databases I would like to find a relatively simple way to do that (in order to put it in a loop). Is it possible to do so?

Thank you,

Federico