Method to group lines

[BlackSun]

Hi,
I have this kind of sheet:
1?? AA1
2?? BB1
3?? CC1
3?? CC2
3?? CC3
3?? CC4
3?? CC5
2?? BB2
3?? CC6
3?? CC7
3?? CC8
1?? AA2
2?? BB3
3?? CC9
3?? CC10
3?? CC11

every rows it's a cell.
The first number is the level of depth.
How can I group group the rows by the level?
I need to use the function "Group" of Excel, so I can hide/show rows.
In this way I would see, before all the 1 then I expand them and I see
only the 2 and so on...

Thanks in advance for your help!

 

[joel]

I usally add 3 auxilary column to the worksheet.. these could be hidde
ofr place and the end of the worksheet in columns IT,IU,IV.

Put these formulas in the columns

IT1 =left(A1,1) 'gets the 1st character
IU1 =mid(A1,2,1) 'gets 2nd character
IV1 =mid(A1,3) 'gets everything after and including the 3r
character


Then copy the formulas down the 3 columns