Timestamp Format Issue

[tnachis]

I am trying to create a rolling 1 Year date range. 

I have realized that when i use this date format datetime20. the date shows ' 01JAN1960:06:09:19'dt.

data null;
format pre_mth End_year instance_date instance_date1 instance_date2 date9.;
pre_mth=%sysfunc(intnx(month,&valdate.,-1,B));
End_year=intnx('day',pre_mth,-365);
call symput('instance_date', "'" || put(End_year, date9.)|| "'dt");
call symput('instance_date1', "'" || put(End_year, datetime20.)|| "'dt");
call symput('instance_date2', "'" || put(pre_mth, datetime20.)|| "'dt");
Run;
%put &instance_date1;
%put &instance_date2;

The goal is to create a date range for instance between ' 01SEP2021:06:09:19'dt and  ' 01SEP2020:06:09:19'dt

[PeterClemmensen]

I'm not entirely sure what a "1 Year date range" and what you're trying to do? 🙂

[Kurt_Bremser · Accepted solution]

Maxim 28: Macro Variables Need No Formats.

If you want to use those values for comparisons/cutoffs in code, the raw value is sufficient and much easier to handle.

end_year is obviously a date, so using a datetime format for it makes no sense and results in times on day zero (1960-01-01).

You should calculate end_year by using YEAR as interval:

end_year=intnx('year',pre_mth,-1,"s");

which automatically takes care of leap years.

So, how do you intend to use these values later in code?