Hi,

Am doing my first project  as a beginner with Filemaker Pro 12 and am stuck at a point. Please help me out on what to do.

am using these fields in a portal:

Opening Stock, Closing Stock, Quantity Received, Quantity Sold and Stock Balance

So

for the first step: Opening Stock = Stock Balance

then for the other steps or next inputs: Stock Balance is to = Quantity Received - Quantity Sold.

Now, at the end inputs (say for 10 rows), the last value of the Stock Balance is automatically the Closing Stock.

Please how can I do this? Is it possible in portal and if not, how can I achieve this

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It would be helpful if you tell us what your solution is supposed to manage in real life terms, as well as list your tables and explain their relationships.