Grand-totals

["gnumeric it actuarcalc com" <gnumeric it actuarcalc com>]

How do I make grand-totals (total of totals or something similar to that)?

There has been a technique permitting to transform a selection by
selecting only the visible cells of a selection. Using outlining, you
could rapidely set up a grand-total structure, opening and closing it at
will to calculate grand-totals using the sum function.

This button exists in Excel but cannot be used anymore to transform a
selection in a sum formula which is being built.Grand-totals are
probably the most useful function for guys who deal with money and the
"visible cell selection" is a very controlled and flexible technique
which could be a real advantage for a spreadsheet for "functional"
power-users. It existed as described in Excel 3.0 but has been de facto
abandoned for a guess method which tries to figure out totalization
level automatically.

Mathias