If date var. ge specific date...

[Maisha_Huq]

Hello,

I have a date variable which I'd like to use as a cut-off to select a set of observations (i.e. exclude all observations after 02/28/2013). The cut-off date will change when I run the program again in the future.

What would be the best way to do this in SAS given the date is stored as the number of days since 1/1/1960?

Would it be to create a variable which will convert my cut-off date to the number of days since 1/1/1960?

Thank you very much in advance for your feedback.

[Reeza · Accepted solution]

As long as your dates are SAS dates (numeric, with date format) SAS can compare dates logically.

Store your reference date as a macro variable and use that in the comparison:

%let cutoff_date="01Jan2015"d;

Then in your code

if date <= &cutoff_date then ...

[Astounding]

A couple of additional considerations ...

If it is possible your DATE variable will have a missing value, be sure to code for that:

if (. < date <= &cutoff_date);

Also, if your cutoff date has a pattern to it, you may be able to omit macro language entirely.  For example, suppose if you run the program in February you would like to include all dates before February 1 and exclude those from February 1 onward.  You could code:

if (. < date < intnx('month', today(), 0);

Under those conditions, you wouldn't need to modify the program at all in the future.  The cutoff date would adjust automatically.

Good luck.

[Maisha_Huq]

Thank you both so much.  That helps, would ve liked to mark both "Correct"