Delivery calculation

[Jalz]

Hi Guys,

I have stock and a deliveries TO in my file. The product has a field called current stock, which for e.g. could be 100.

The deliveries table may a several records, each with a date and number of items. What I would like to do is calculate how many items are remaining from each delivery.

So for Eg.

Stock Table Occurance

Current Stock = 100

Delivery Occurance (4 records for example)

1) Date 1/4/2007 Number Delivered 50 [calculated field should say 50]

2) Date 1/3/2007 Number Delivered 20 [calculated field should say 20]

3) Date 1/2/2007 Number Delivered 10 [calculated field should say 10]

4) Date 1/1/2007 Number Delivered 40 [calculated field should say [color:red]20 not 40 as the current stock is 100 and not 120, first in first out approach]

Any help much appreciated. I have also included a file to show you what I mean as I think Ive not explained it very clearly.

delivery.zip

[Jalz]

Not to worry guys, Ive worked it out using getnthrecord and a relationship which is sorted decending.