Re: st: How to count countries by year

[Chris Parker <cparker.phd2007@london.edu>]

Hi Emanuele,

Assuming you have one observation per year per state you should be
able to do the following

bysort year: gen numcountry=_N

Chris

Chris Parker

________________________________

PhD Candidate | Management Science & Operations
London Business School | Regent's Park | London NW1 4SA | United Kingdom
Direct line +44 (0)20 7000 8816 | Email cparker.phd2007@london.edu

On Fri, Mar 4, 2011 at 10:28 AM, emanuele mazzini
<madsoenistata@gmail.com> wrote:
>
> Hi there.
> I occurred in a little problem in counting the observations of my
> dataset. I have panel data and need to count how many countries are
> there for each year. I tried with the following command (assuming that
> cty1 is the name of each country):
>
> bys year: count if  cty1[_n]!= cty1[_n-1]
>
> but Stata gives a result which is not what I was expecting.
> Can anybody help?
> Thank you everyone in advance,
> Emanuele Mazzini.
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