Filter by Value in a Value List Contained in a Portal
I'm working within a personnel database. I am trying to create a record of each employee's time off. To do so, I have a main layout called "Personnel" with tabs on it for different details about each employee. One of the tabs is titled "Time Off" and it has a portal on it which displays every set of time an employee takes off. The admin can add to that list by using an add button.
Within the portal there is a field called "Type" which is a drop down menu from a value list called "Type of Time off". The value list has five options for types of time off. There are no special parameters to the value list, it only drops down and then displays the value chosen.
How can I filter the portal to only show vacation time off? I need this to be an interactive function so a user could choose vacation, see a total number of vacation days an employee took, then change the filter to "sick leave" and see the total sick leave days the employee took off.