Increment of an itemtype

Hi,
Is there a way to set the itemtype if an item to be incremented by a certain number based on the previous set itemtype. Example: an item is generated from a source with an itemtype of 1, the second item coming out should have its itemtype set to the value of the previous itemtype (1) + a set number. A for loop wouldn't work. Is there a way to do that?
Thanks

Hello George,

write the itemtype of previous item in a numberlabel, set the itemtype of next item in the OnExit-Trigger to the incremented value and update the numberlabel.

Jrg

Hi Jrg,
Thanks for the reply. I was thinking the same way that you mentioned in the reply, but where I'm getting stuck is updating the itemtype after updating the label, see attached model. I can't think of a way to do it except a loop which it won't work here.
Thanks for the help.
George

I believe Jorg was implying that you use a label on the Source to remember the last value. I have attached an update to your model.

Depending on what you are doing you might be able to base the itemtype on the output of the Source in the OnExit trigger. See attached.