On Time Delivery Query



I'm trying to create a query for "On Time Delivery". I have query fields of PO, Date Received, Due Date and Date Shipped. I'd like to calculate EARLY (shipped 3 days early from the due date), On Time (Shipped on Due Date or 2 days early) and LATE (Shipped past Due Date) and on a business days only (excluding Saturday and Sunday). These are all coming from 3 different tables. I would appreciate any ideas.

Thanks,

John

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