st: Creating long, filledin dataset from two, year variables

["Kevin O'Connell" <kevocon@gmail.com>]

Hi,
I am trying to move a dataset that was built with a start year, start
year population and end year to having a long format.  I guessed this
was a double-wide dataset, but I couldnt get my variables to match up,
or to fillin .

  id     pop          startyear endyear
1       11000   1818            1822
2       1500            1820            1824
3       15000   1820             1823
4       2200            1821            1836
5       2000             1821   1840
6       125000  1821             1828

I am trying to get the dataset into this format so I can fill in
missing variables for population over the time span between start and
end:

id  year pop
1 1818  11000
1 1819
1 1820
1 1821
1 1822
2  1820  1500
2  1821
2  1822
2  1823
2  1824

and so on.
There are about 5000 years within 500 id, so I am hoping to find a
better solution that data entry, but i dont know the right
term/command for what I am trying to do.

Thanks,
Kevin

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