Version Formula in Module
Answers

I assume you mean applying version calculations to line items, vs line item subsets.
In any case, depending on your use case, I'd say you're better off using a boolean line dimensioned by version to determine what calculation to run.
E.g. IF List Attribute  Version.Version = Actual THEN X ELSE IF List Attribute  Version.Version = Forecast THEN Y
Gives better auditability of your logic, is likely more maintainable and gives you the flexibility to group logic (e.g. if multiple versions use the same calculation, you can have a boolean that triggers the same calculation for all the likeversions).
The performance implication is probably less clear, but will depend on your usage.
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Hi, @tompatrick.ting
You might want to read this best practice.
Line item subsets demystified  Anaplan Community
I owe the article much.
Regards,
Taichi
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