Obsidian | Level 7

Identify dates that fall in last week of the month

How do I identify dates that fall in the last week of the month?

```How do I identify dates that fall in the last week of the month?

DATA dates;
INPUT startdt :mmddyy10.;
FORMAT startdt mmddyy10.;
DATALINES;
12/01/2000
09/30/2012
06/01/2001
09/01/2001
09/30/2018
09/30/2018
04/30/2017
;
RUN;```

1 ACCEPTED SOLUTION

Accepted Solutions
Super User

Re: Identify dates that fall in last week of the month

``````
DATA dates;
INPUT startdt :mmddyy10.;
first=nwkdom(5,2,month(startdt),year(startdt));
in_last_week=(startdt>=first);
FORMAT first startdt mmddyy10.;
DATALINES;
12/01/2000
09/30/2012
06/01/2001
09/01/2001
09/30/2018
09/30/2018
04/30/2017
;
RUN;``````
5 REPLIES 5
Diamond | Level 26

Re: Identify dates that fall in last week of the month

Please let us know how you define "week". Does it start on Saturday, or Sunday, or Monday? Or do you mean last 7 days? Or do you mean something else?

--
Paige Miller
Opal | Level 21

Re: Identify dates that fall in last week of the month

If you mean the last 7 days of the month, here's a way:

``````data want;
set have;
if (intnx('month', startdt, 1) -7) <= startdt < intnx('month', startdt, 1);
run;``````
Super User

Re: Identify dates that fall in last week of the month

Assuming last 7 days.

``````data want;
set dates;
in_last_7days = startdt >= intnx('month', startdt, 0, 'e') - 7;
run;``````
Super User

Re: Identify dates that fall in last week of the month

``````
DATA dates;
INPUT startdt :mmddyy10.;
first=nwkdom(5,2,month(startdt),year(startdt));
in_last_week=(startdt>=first);
FORMAT first startdt mmddyy10.;
DATALINES;
12/01/2000
09/30/2012
06/01/2001
09/01/2001
09/30/2018
09/30/2018
04/30/2017
;
RUN;``````
Obsidian | Level 7

Re: Identify dates that fall in last week of the month

Thanks you so much @Ksharp Ksharp.  This is exactly what I was looking for.  To be able to identify the start date of the last week of the month.  I wasn't aware of the NWKDOM function.  Than you for bringing it to our attention!!!

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