Thanks Blake. your flowchart and guidance have given me some ideas !!!
manage to work out with less tables (not sure if this concept is similar to your thought process)
what i did
1. Product (master) connects to product movements (child)
2. summarise monthly movement into Master table (12 new summary fields)
3. Create accumulated fields for each month against each product in product table (another 11 new summary fields)
4.create accumulated lookup fields in Product Movement table (child) for each month (12 new lookup fields)
5. create a formula field to workout the balance each record should pick up
6. Month table (master) connects to Product movement table (child)
7. Create average summary field for each product in month table
i will then get the below table on Quickbase that calculates the accumulated usage in each month for each product which is identical to Excel
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Leon Wong
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