How to group data from one column?

I don't think there is a criteria that combines the departements with each other. I am looking for 3 groups in which I can place these departments (For example :primary process,Secondary and administrative process) 

Is there a formula where I can make a Table and filter particulair departements into that table?

So the columns are like this 

Column

Date Column Department Column Employees Column Phones active at department

11-02-16        Sales                           110                         60 

11-02-16        Purchase                     60                            40

11-02-16        Bosses                         4                             4

18-02-17        Sales                           110                         60 

18-02-17        Purchase                     60                            40

18-02-17        Bosses                         4                             4

28-03-17        Sales                           110                         60 

28-03-17        Purchase                     60                            40

27-03-17        Bosses                         4                             4

I want to place Sales and Purchase in a Table together and name it Primary process, So i can show how many % of the Primary process uses a phone and filter on it.

I want to make a chart which shows me the information of my whole company and in which I can zoom in on the 3 groups and then zoom in on the departments.