In addition to other answers, see -dropmiss- from STB-60. 
Nick
[email protected] 
Andrea Bennett
A quick question related to dropping variables: I would like to drop a  
variable when a certain condition is met (I'm using loops to check  
whether a variable is not empty for each year of observation). AFAIK, - 
drop- and -keep- only refer to observations if being used  
conditionally, e.g. I cannot use "drop THISVAR if mean_THISVAR<1".
So, how can I drop a variable when a certain condition is met?
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