How to create unbalanced panel data based on start date and end date

Question

My data looks something like this:

leader   startday       enddate
P       28/12/2000      15/12/2004
C       11/11/1966      19/10/1969
H       21/10/1993      1/07/1994

And I would like to obtain the following data:

leader      year
P          2000
P          2001
P          2002
P          2003
P          2004
C          1966
C          1967
C          1968
C          1969
H          1993
H          1994

Answer 1

As you didn't specified language to use. I'll write some pseudo-code to help you with it.

get_year(string date){
   return int(date.substr(date.lastIndexOf('/')+1));
}

foreach (table as row) {
   for ( int year = get_year(row.startday); year <= get_year(row.enddate); year++ ) {
      print( row.leader + " " + year );
   }
}