Tracknumber & Discnumber Format / of x parameter

Hi,
just wanted to know if there is an easy way of displaying and setting the Total Tracks number? The same goes for Total Discs. Others may have come accross this, like I did, that you can set these parameters in e.g. in iTunes, but I can't see this in mp3tag. I have also looked but could not find a way in mp3tag to display more coloumns than the 34 odd that one can via View-Customize columns.
Right now, I display all tag info via the column selection and it would be great if one could also show the Total Tracks and Total Discs (other tag fields as well?).

If I have just overlooked something, could someone please point me in the right direction?

There are no special fields in V2.3 for total tracks and total discs but they are part of the field TRACK or DISCNUMBER and separated by the slash.
I think there is already a column for TRACK.
You can easily create a new one with exactly the function you mentioned for %discnumber%