Default combo box based on previous record

[eabler]

I have a single view form, and each record lists project information. Each
project can be assigned to 1 of 3 people on a team- chosen from a value list
combox on the form. I would like the combobox to default to the next team
member. I.e., if the last project is assigned to team member 1, then this
project is assigned to team member 2 but I cannot find any code to do so. I
can only find code to default the combo box to the previous record value, not
the next item on the list. Perhaps a conditional statment using itemdata?
But how do I base the condition on the previous record?

 

[eabler]

The combo box is bound to a field in my underlying table.