I have the following repeating table:

COST has a bunch of rules set up. The COST is based on the ITEM selected. The rules work fine. Problem is, when I select the ITEM and type in the QTY, nothing appears in COST until I tab into COST, type something, then tab out. It doesn't matter what I type, it is overwritten by the rule. Like I said, the rules work fine. They show the appropriate costs for the item, but I want COST to populate immediately when the ITEM is selected, not after I "trick" the form and have to type something in the block. Is that possible?