Note by: Oliver Fust
Excel constants:
&A = &[Tab] = Tab Name
&D = &[Date] = Date
&F = &[File] = File Name
&N = &[Pages] = Total # of Pages
&P = &[Page] = Page Number
&T = &[Time] = Time
&W = &[Path] = Working Directory (Path)
example:
$worksheet->setFooter('Page &P of &N');