Thank you both Comatt1 and hilfy for taking the time to assist me.
I will try both your suggestions and post back as soon as I can.
Hilfy, to answer a couple of your questions:
The main category is always 3 digits followed by a decimal and the sub categories are always the first 3 digits of the main category a decimal and then 4 more digits (ie: 100.1234). I'm actually dealing with assets/equipment & I apologize for not being very clear on that, but I was trying to make my example as simple as possible. I should also add that not all main categories will have a sub category.
I have everything grouped by the first 3 digits but when I try to return the main category name, I get the name of the sub category for the first item in the group. I understand what you're saying about sorting on the category field but I need the list to sort by the AssetId nbr so I don't think that your suggestion will work. I will try it though just to make sure.
As for whether I want subgroup data to appear in the report at all, I do definitely need to include it so a filter won't work.
I will let you know how I make out.
Again, thank for your assistance. It is greatly appreciated.