Generate year-variable

[Jonas Meyer]

I have a rather simple question:

I have a date variable like "01/08/2007", how should the code look like if I want to drop all observations which are not observed in 2007?

Alternatively how can I generate a new variable which only consist of the year from the date-variable above?

Hope someone has an answer?

/Jonas

[Svend Juul]

If your date variable (bdate) is numeric (although displayed in date format):

generate byear = year(bdate)
keep if byear==2007

If the date variable (sdate) is string, you must create a numeric date variable first:

generate bdate = date(sdate,"DMY")         // or "MDY" if that is the sequence

[Nick Cox]

If that variable is a string, then

 
gen year = real(substr(sdate, -4, 4))

should suffice. No need to create a daily date variable first.

[Jonas Meyer]

Thank you Svend