How can I get table column actual width from xml excel 2003?

I need read column width and row height from xml excel 2003 for printing.But I found that is no law.

Fox example:

    Open a xls file and set columns width 1mm、2mm、3mm、4mm、5mm.Then file save as  xml excel 2003.Open xml file，the value of  columns were 9.6、15、23.4、25.8、31.2.It is no law.

    How can I get table column actual width from xml excel 2003?