Saving a Custom Table Style

This doesn't help my situation. (Also, Ctrl-F12 gives me Open, not Save As.)
I'm looking to create settings for my table so I don't have to create them manually every day. I get a 100,000 row spreadsheet every day with new data, 894 columns today, and growing. I set it to have vertical, bold, 11 point headings, and the body to have 9 point Arial Narrow, set View to freeze panes to freeze the first row and first two columns, convert it to a table, the heading has wrap Text, body doesn't, I use the default shading and colors when I convert it to a Table, then set the column width to fit the contents excluding the header row, with a minimum of 4 characters (which I do using a row of "xxlx" in each cell two rows below the table). It can take quite a while, 15 minutes, to get the file opened, Editable, and set as a table that way, before I can start using it. Would love to speed up and simplify that process.

Is it possible to create a table style or template that includes subtotals of columns at the bottom and/or subtotals of rows at the right? Is it possible for there to be multi-level subtotals? If there are multi-level subtotals, is it possible to have the multi-level subtotal rows to include both key values and descriptive values shown?

For example, I have attached an image of a Regional & Departmental Costs spreadsheet with two levels of subtotals. I have highlighted in yellow the cells that contain subtotals. I needed to manually add the Region Key, Region Description, and Department Descriptions for the Departmental subtotals and I needed to manually add the Region Description for the Regional subtotals.

I have been able to write macros to do this but instead I would like to find if there are any options within Excel that will automatically add these values to the subtotal lines. Perhaps a table style or template could be set up that would use such an option. Thank you for your suggestions.
(see Figure 1 below)

Gary

If you save it as Book.xltx in your Excel Startup folder, the custom style will be available in the table > design > table styles the next time you need it in a newly created workbook.

The template does not need to contain the actual table.
ie using a current New worksheet (in case you have already saved some settings),
Option1:-
- insert an additional sheet
- create the table with a custom design saving the design
- delete the new sheet
- save the new workbook in your excel startup folder as Book.xltx
Option 2 - it you have already created the custom design in a different workbook
- Go to the sheet in the workbook with the custom table
- Right click on the Tab with you table and copy it to the New workbook
- Delete the sheet from your New workbook
- save the new workbook in your excel startup folder as Book.xltx