Grouping Initiatives

Hello Riga!

I have set up an Initiative → epic → Story/task → Task hierarchy to capture time spent across initiatives and also by team/team member as in the image below

What I would like to do is to create a report that groups these Initiatives into broad categories for budgeting purposes. What would be the easiest and fastest way to go about it? I am looking for a way to group these initiatives; is using Aggregate the right way to go?