MDX Weighted Counts

I have a simple fact table that is used to count completed orders. The fact table uses conformed dimensions Employee and OrderType. I want to create a calculated measure that will weigh the completed order count for each employee. The weight is determined by the order type (i.e. new = 1.5, change = .75, cancel = .5). I want the calculation to be dynamic, so I was thinking of storing the weight in the dimension table, then using the weight in the MDX expression. Will this work? Or, maybe there is a better approach. Thanks