How to use another table for Calculated/Formula Fields

Hi,

I created Table A which contains the fields(please see attachment for more details):
Stem(Text Field)
Region(Text Field)
Country(Text Field)
Date 1(Number Field)

Table A is the parent table of Table B. Table B Contains the fields:
Date(Date Field)  -> User input
Stem(Text Field) -> Drop Down
Region(Text Field) -> Drop Down
Country(Text Field) -> Drop Down
Calculated Date(Date Formula field) - Current Formula is "AdjustMonth([Date],)"

Basically, the setup is when a user fills data for Date, Stem, Region and Country in Table B, the Calculated Date field should result in the Date based on the formula above. However, I cannot seem to select the correct record in Table A based on the inputs(Stem, Region and Country) of the user.

I have used the reference field for Table B, but it just provides a dropdown of all the records in Table A. This should not be the case as the reference field should be filtered based on the fields (Stem, Region and Country in Table B) which would select the respective record in Table A

As an example, a user selects the following in Table B:
Date = April 1, 2021
Stem = 1
Region = Region A
Country = Country A

The Calculated Date should result to June 1, 2021 which is 2 months after April 1, 2021 without manually adjusting the reference field in Table B. 

Hope this makes sense. Thank you for the help!




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Paul Tria
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