How to find the difference between two date attributes in eText template

Summary:

We need to find out the difference between two dates and add 1 to the result in eText template.

Content (required):

We need to find out the difference between two dates and add 1 to the result in eText template.

Version (include the version you are using, if applicable):

Code Snippet (add any code snippets that support your topic, if applicable):

Example:

(Absence_End_Date - Absence_Start_Date ) +1

But it is not working as expected.