Hello, this is Max Kim.
Now I am running a panel data with year and age.
However, the data for age only exist for the first year of the data.
Like this

year AGE
1999 76
2001 78
2003
2005
2007
2009
2011
2013
2015
2017
1999 76
2001
2003
2005
2007
2009
2011
2013
2015
2017


I do want to fill the rest part,,,