What is the Item "Commission Group Field"?

Hi

Rookie here, so please forgive if this a dumb question.

In researching NAV (5.0) commission capabilities I've run into several references to the item "Commission Group" field. These references are in the Help - and the (characteristically obvious/useless) explanation is:

Here you can enter a number that can be used to assign items to commission groups.

It's also referenced in the help for both the Inbound and Outbound Product Catalog Line Tables:

This field is read-only. Therefore, you cannot enter anything in it. For further information, see the Help for the corresponding field in the Item table.

The field does not appear on the (North America ver) item card (but you can se it if you zoom) and I can find NO information on what it is for. ](*,)

At this point I know that I've spent the requisite amount of time on this to guarantee that anything I do learn will be useless, but ...

Any info would be appreciated.

Bob