Dashboard Chart

I have added a custom field ‘Directorate’ in the attendance Doctype, now I am not able to create a chart as per the directorate. Here is the Screenshot.

custom Field ScreenShort.

Dashboard chart Screenshot.

I created a parent department or linked it with our department. Let’s understand with the example. I have a department called Accountant or its parent department is Head Accountant. After that I added this department to the employee or I created a director custom field on it. After which I fetched the value of parent department Succesfully, after that I created a custom field on the doctype of attendance or gave the director name and fetched the value from employee master. Now I have created a chart in which group by department and not parent department has to be chosen. I want to choose parent Department in the group by, How to achieve this?

I think, Directorate is the data field.