Hi Dean,
You can get the last five positions of the Employee number by using a combination of substring and string-length:
Example: substring(EmployeeNumberfield; string-length(EmployeeNumberfield) - 4; 5)
If you only want to show the employee number that are 5 positions long, then it will be much easier to do that in code with an if-statement.
Hope this helps,
- Samir -