Dropping values within range, while preserving others.

[Moos Janssen]

I am quite new to Stata and did some thorough research on how to do the following, but didn't seem to get it done properly.

Currently I am trying to clean my dataset which looks something like this:

ID	Year	Cash
1	2008	20
1	2009	23
1	2010	21
1	2011	18
2	2009	52
2	2010	51
2	2011	50
3	2009	12
3	2010	14

I want to keep only the ID's that include all of the years 2008-2011 and drop all observations that only have a subset of those. (my dataset is far bigger than this, hence dropping manually doesn't work)

However, everything I tried has not worked out so far so I was hoping one of you could help me out a bit here.


Cheers,

Moos

[Andrew Musau]

Assuming that there is no year that precedes 2008:

isid ID Year
bys ID (Year): gen tag= Year[4]==2011
keep if tag

If there are years preceding 2008 in the sample, you need to create an indicator for the 4 year period and then proceed as above.