When you want to add a new balance type, you need to go to Administration --> Reporting types --> Add new --> Balance type:
You will need to set a name for the balance type, unit, and limits:
So if you set a balance like the one from above, it means that when you add the balance to an employee, there can be no less than 0 vacation days and no more than 21. For static balances, you can find more info here:
https://cozone.freshdesk.com/a/solutions/articles/15000048014
The same goes for the other units:
Existing balance types can be seen in Administration --> Reporting types --> Balance types:
