st: monthly moving average

 From Ana Gabriela Guerrero Serdan To statalist@hsphsun2.harvard.edu Subject st: monthly moving average Date Mon, 26 Mar 2007 12:12:22 -0700 (PDT)

```Dear all,

Im rising a question again.I hope you understand as Im
new to Stata and Im learning. I want to create a
program that will calculate the proportion of women or
men as a moving average. This proportion will move per
month.

So basically the first proportion is the number of
women in my data would include months 1-12  for years
1,2,3. The second include months 2-12 for year 1 and
months 1-12 for years 2 and 3. The third would be the
proportion of women in months 3-12 for year 1 and
months 1-12 for year 2 and 3. Etc...

I have 60,000 observations and looks like:

list	month year  female male sex_unknown

+-----------------------------------------+
month   year   female   male   sex_un~n
-----------------------------------------
1.	7   2005        0      0          1
2.	9   2004        0      0          1
3.	6   2006        0      0          1
4.	3   2005        0      0          1
5.	9   2005        0      0          1
-----------------------------------------
6.	5   2005        0      0          1
7.	1   2006        0      1          0
8.	4   2004        0      0          1
9.	3   2005        0      0          1
10.	8   2003        0      1          0
-----------------------------------------
11.	11   2003        0      1          0
12.	11   2005        0      0          1
13.	8   2006        0      0          1
14.	6   2005        0      0          1
15.	10   2006        0      0          1
-----------------------------------------
16.	9   2005        0      1          0
17.	7   2005        0      0          1
18.	5   2003        0      1          0
19.	3   2004        0      0          1
20.	12   2004        0      1          0

Im trying to  do a simple program like this:
______________________________________
program mvafemale
version 9.2
proportion female if month==1-12 & year==2003-2006,
over(year)

.....// I want to calculate the proportion for all
moving average months

end

mvafemale
_________________________________________

However, when I calculate the first proportion it says
that there are no observations.  I have tried a few
other versions but got stuck.

Can anyone recommend me something?

regards,
Gaby

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```