I have tested some applications, how they behave if the parameter of the IRR function is a reference list, aka the result of the union operator. The test file is attached.
Excel: The two cell strips are concatenated in the order given in the union. When you manually join the values to one cell strip and use that as input to the IRR function, the result is the same.
PlanMaker NX: Only the left cell strip is used in the calculation. I have reported this as bug to SoftMaker.
Google Sheets, LibreOffice 27.2 , Collabora, Gnumeric 1.12.56, OnlyOffice 9.3.1.8 (x64 exe): They result an error for the case the parameter is a union of cell strips.
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Regina Henschel
The Document Foundation
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