Add mesaures when Column Removed

Hi tkrupka ,

Based on your addtional information, we can try to use the following measure and do not need to create other calculate column.

LastDayTankLevel2 =
VAR IBXID =
    LOOKUPVALUE ( IBXs[IBX_ID], IBXs[IBX_Name], SELECTEDVALUE ( IBXs[IBX_Name] ) )
RETURN
    SUMX (
        SELECTCOLUMNS (
            FILTER ( ALL ( Tanks ), [fk_IBX_ID] = IBXID ),
            "tID", [fk_GeneratorName_ID]
        ),
        CALCULATE (
            LASTNONBLANK ( RunData[DT_Level], 1 ),
            FILTER (
                RunData,
                AND ( RunData[fk_IBX_ID] = IBXID, RunData[fk_GeneratorName_ID] = [tID] )
            )
        )
    )

or the two in one formula version

LastDayTankLevel3 = 
VAR SelectedTank =
    SELECTEDVALUE ( Tanks[Tank_Name] )
VAR SelectedGenerator =
    LOOKUPVALUE ( Tanks[fk_GeneratorName_ID], Tanks[Tank_Name], SelectedTank )
VAR IBXID =
    LOOKUPVALUE ( IBXs[IBX_ID], IBXs[IBX_Name], SELECTEDVALUE ( IBXs[IBX_Name] ) )
RETURN
    IF (
        ISINSCOPE ( Tanks[Tank_Name] ),
        CALCULATE (
            LASTNONBLANK ( RunData[DT_Level], 1 ),
            RunData[fk_GeneratorName_ID] = SelectedGenerator
        ),
        SUMX (
            SELECTCOLUMNS (
                FILTER ( ALL ( Tanks ), [fk_IBX_ID] = IBXID ),
                "tID", [fk_GeneratorName_ID]
            ),
            CALCULATE (
                LASTNONBLANK ( RunData[DT_Level], 1 ),
                FILTER (
                    RunData,
                    AND ( RunData[fk_IBX_ID] = IBXID, RunData[fk_GeneratorName_ID] = [tID] )
                )
            )
        )
    )

If the result is still not match your expeted one, just  figure it out.

BTW, pbix as attached.

Best regards,

Community Support Team _ Dong Li
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