Can excel update date when document last changed?

I am trying to figure out how to have a date showing in excel for when
document was last updated. I know you can have date in the footer but that
just shows current date when document is opened. I want date to only change
to current if document has changed.

Hi Nic

Would this help you out
Sub date_last_modified()
date_modified = ActiveWorkbook.BuiltinDocumentProperties("Last Save Time")
date_modified = Format(date_modified, "dd/mm/yyyy")
'MsgBox date_modified
'or insert in a cell of your choice
'range("c1").select
'activecell=date_modified
''
'or insert in a center footer
For Each wsheet In Sheets
'the default date format is m/d/yy h:m:s AM/PM
'alternate format is m/d/yy h:mm am/pm
date_modified = Format(date_modified, "dd/mm/yyyy")
wsheet.PageSetup.CenterFooter = "Last Modified: " & date_modified
Next wsheet

End Sub