Learning Resource Alerts-is there a formula to specify # of Overdue Days within Message Template?

We have a custom Learning Resource Alert in Alerts Composer that triggers to learners every two weeks and notifies them of all overdue learning they have (up to a Due Date of 365 days ago). Within the Message Template all the learner's overdue learning is grouped in a table that displays the Learning Item Title and Due Date. I would be interested to know if we can also include a table column that shows "Number of Days Overdue". This column should display calculated values to specify by how many days exactly the item is overdue (something like sysdate - Due Date).