Macro To Name Range That Isn't Pre-defined

I need the macro to create a named range based on a last column and row that can change. It won't change once the report is set up, but since this is a template that will be used for hundreds of projects, it needs to be flexible to accomodate a varying numbers of columns or rows

The starting cell will always be A10, but the ending cell can change depending on how many columns and rows are in the table.

Right now, the code I've created is

Sub NamePivotData()
Dim LCol As Long
Dim LRow As Long
Dim RngEnd As Long

[Code].....

I need it to refer to ='Calendar Setup'!$A$10:$*$** where * is the last column in the table and ** is the last row in the table.