Difference of SAS dates

[Zatere]

Hi there,

I am working with SAS dates.

I have the following data which represent the opening and closing dates of some businesses. 

Opening_Date	Closing_Date
19/02/1955	19/02/2020
23/03/1955	23/03/2025
23/03/1955	23/03/2025
28/11/1956	28/11/2026
13/04/1954	13/04/2019

The dates in the SAS data set are character so I used the following code to convert them in numerical form:

Opening_Date_New = input(Opening_Date, ddmmyy10.);

Closing_Date_New = input(Closing_Date, ddmmyy10.);

Later in the program, based on some conditions I want to create an Expected_Closing_Date, which is calculated by adding 80 years to the Opening_Date_New. For that I use the following code:

Expected_Closing_Date = intnx("year", Opening_Date_New, 80, 'sameday');

In a Data Step I format the dates by using the following code:

format Opening_Date_New yymmdd10. Expected_Closing_Date yymmdd10.;

I end up having the data attached, which look like as below:

Opening_Date    Closing_Date         Opening_Date_New    Expected_Closing_Date
19/02/1955	19/02/2020	     19/02/1955	    19/02/2035
23/03/1955	23/03/2025	     23/03/1955	    23/03/2035
23/03/1955	23/03/2025	     23/03/1955	    23/03/2035
28/11/1956	28/11/2026	     28/11/1956	    28/11/2036
13/04/1954	13/04/2019	     13/04/1954	    13/04/2034

I am trying to calculated the difference between the Opening_Date_New and Expected_Closing_Date but I am getting an error:

data want; 
set have;
Diff = intnx('year', Opening_Date_New, Expected_Closing_Date);
run;

NOTE: Invalid argument to function INTNX('year',-1777,27443) at line 139 column 8.

Any help please?

Thanks

[PabloNogueras · Accepted solution]

You are using the incorrect function.  Use the following instead.

Diff = intck('year', Opening_Date_New, Expected_Closing_Date);