Matrix add Custom column

Hi, H_insight 

May I ask if this is the expected output you are looking for? Based on your description, I have created many measures to achieve the effect you are looking for. Following picture shows the effect of the display.

Measures:

YTD =

VAR _today =

    TODAY ()

VAR _yearStart =

    CALCULATETABLE (

        STARTOFYEAR ( Financial[Date].[Date] ),

        Financial[Date] = YEAR ( TODAY () )

    )

VAR _sales =

    CALCULATE (

        SUM ( Financial[Sales] ),

        Financial[Date] <= _today

            && Financial[Date] >= _yearStart

    )

VAR _cost =

    CALCULATE (

        SUM ( Financial[COGS] ),

        Financial[Date] <= _today

            && Financial[Date] >= _yearStart

    )

RETURN

    SWITCH ( SELECTEDVALUE ( 'DataNeed'[Data] ), "Cost", _cost, "Sales", _sales )



PeriousOneWeekMonday =

VAR _today =

    TODAY ()

VAR _periousOneWeek =

    TODAY () - 7

VAR _periousOneWeekday =

    WEEKDAY ( TODAY () - 7, 2 )

VAR _periousOneWeekMonday = _periousOneWeek - _periousOneWeekday + 1

VAR _sales =

    CALCULATE (

        SUM ( Financial[Sales] ),

        Financial[Date] <= _PeriousOneWeekMonday + 4

            && Financial[Date] >= _PeriousOneWeekMonday

    )

VAR _cost =

    CALCULATE (

        SUM ( Financial[COGS] ),

        Financial[Date] <= _PeriousOneWeekMonday + 4

            && Financial[Date] >= _PeriousOneWeekMonday

    )

RETURN

    SWITCH ( SELECTEDVALUE ( 'DataNeed'[Data] ), "Cost", _cost, "Sales", _sales )



PeriousTwoWeekMonday =

VAR _today =

    TODAY ()

VAR _periousOneWeek =

    TODAY () - 14

VAR _periousOneWeekday =

    WEEKDAY ( TODAY () - 14, 2 )

VAR _periousOneWeekMonday = _periousOneWeek - _periousOneWeekday + 1

VAR _sales =

    CALCULATE (

        SUM ( Financial[Sales] ),

        Financial[Date] <= _PeriousOneWeekMonday + 4

            && Financial[Date] >= _PeriousOneWeekMonday

    )

VAR _cost =

    CALCULATE (

        SUM ( Financial[COGS] ),

        Financial[Date] <= _PeriousOneWeekMonday + 4

            && Financial[Date] >= _PeriousOneWeekMonday

    )

RETURN

    SWITCH ( SELECTEDVALUE ( 'DataNeed'[Data] ), "Cost", _cost, "Sales", _sales )





PeriousThreeWeekMonday =

VAR _today =

    TODAY ()

VAR _periousOneWeek =

    TODAY () - 21

VAR _periousOneWeekday =

    WEEKDAY ( TODAY () - 21, 2 )

VAR _periousOneWeekMonday = _periousOneWeek - _periousOneWeekday + 1

VAR _sales =

    CALCULATE (

        SUM ( Financial[Sales] ),

        Financial[Date] <= _PeriousOneWeekMonday + 4

            && Financial[Date] >= _PeriousOneWeekMonday

    )

VAR _cost =

    CALCULATE (

        SUM ( Financial[COGS] ),

        Financial[Date] <= _PeriousOneWeekMonday + 4

            && Financial[Date] >= _PeriousOneWeekMonday

    )

RETURN

    SWITCH ( SELECTEDVALUE ( 'DataNeed'[Data] ), "Cost", _cost, "Sales", _sales )



PeriousFourWeekMonday =

VAR _today =

    TODAY ()

VAR _periousOneWeek =

    TODAY () - 28

VAR _periousOneWeekday =

    WEEKDAY ( TODAY () - 28, 2 )

VAR _periousOneWeekMonday = _periousOneWeek - _periousOneWeekday + 1

VAR _sales =

    CALCULATE (

        SUM ( Financial[Sales] ),

        Financial[Date] <= _PeriousOneWeekMonday + 4

            && Financial[Date] >= _PeriousOneWeekMonday

    )

VAR _cost =

    CALCULATE (

        SUM ( Financial[COGS] ),

        Financial[Date] <= _PeriousOneWeekMonday + 4

            && Financial[Date] >= _PeriousOneWeekMonday

    )

RETURN

    SWITCH ( SELECTEDVALUE ( 'DataNeed'[Data] ), "Cost", _cost, "Sales", _sales )



FourWeek = [PeriousOneWeekMonday] + [PeriousTwoWeekMonday] + [PeriousThreeWeekMonday] + [PeriousFourWeekMonday]

If this does not work, could you please share some sample data without sensitive information and expected output.
How to provide sample data in the Power BI Forum - Microsoft Fabric Community

Best Regards,
Yang
Community Support Team

If there is any post helps, then please consider Accept it as the solution  to help the other members find it more quickly.
If I misunderstand your needs or you still have problems on it, please feel free to let us know. Thanks a lot!

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