Use custom format 0000 type 1,2  etc

Click on the column header letter where you want your list.
Format > Cells > Number Tab
In the left panel highlight 'Custom'.
On the right, where it says Type: type 0000, click 'OK'
In the first cell of your column type 0001,
With this cell highlighted, Edit >Fill > Series.
Dot in Column, Step value: 1, stop value 2400. click 'OK'

(Try it on a copy of your file first).

George Gee

Enter  '0001 in A1  Note the apostrophe.

Type A1:A2400 in namebox and ENTER.

Edit>Fill>Series>Autofill

Gord Dibben  MS Excel MVP

Hi Rita & Matt,

If you go into Format/Cells/Numbering and then select Text it will allow you
to type anything.  Type in 0001, next cell down or across or where ever you
need it to be & type 0002.  Highlight both cells.  At the bottom of the
second cell will be a little knob that you can pull down and it will then
create all the numbers up to what ever you need.  You can then align the
cells to suit your needs.

Hope this helps

Cheers
Donna