How to create horizontal subtotals ??

[Ursula A.]

I want to create horizontal subtotals for example from A to K??
The default menu in Data - Subtotal only seems to work for subtotals from
top to bottom.

 

[Luke M]

You can just write the formula, you don't have to use the menus.

=SUBTOTAL(9,A2:K2)

For help on which function number to use, just see the XL help file.

 

[Ursula A.]

The option Data - subtotals is a special function that not only adds the
numbers, but also enables to collapse and hide the data between the
subtotals. You will then see some lines and numbers for each level in the
grey area beside the excel table.

What I want to do now is to do this across the worksheet, so it collapses
accross the worksheet, and not from top to bottom.