Dax Needed for Trailing Twelve Months

[PBI-Curious]

Hello PBI Community-  Good Day!

I currently using a TTM Dax measure ( see below) that is giving me a ( YoY $) for 11 months instead of 12 months. I tried changing the -11 to -12, but it still doesn't give me the correct (YoY $) I'm looking for.

Note:

I confirmed the Dax measure was calculating a (YoY $) for 11 months by exporting the data and creating a schedule in Excel. Making the adjustment in my Excel formular to calculate a (YoY $) with 12 months of data (by month year) yielded the correct (YoY $)

How would I tweak this measure or should I use another approach.

TTM CY = CALCULATE(SUM('SnR 2018 - 2021'[SnR Amount])

    DATESBETWEEN('Calendar'[Date],

FIRSTDATE(

DATEADD(

LASTDATE('Calendar'[Date])

,-11,MONTH

)

),

LASTDATE('Calendar'[Date])

)

)

[Fowmy]

@PBI-Curious 

Can you try this measure? Share some data with the expected results if this doesn't

TTM CY = 
    CALCULATE(
        SUM('SnR 2018 - 2021'[SnR Amount]),
        DATESINPERIOD(
            'Calendar'[Date],
            MAX('Calendar'[Date]),
           -12,
           MONTH
        ),
        ALLSELECTED('Calendar')
    )

work.

[PBI-Curious]

Fowmy

Much appreciate your help!

Thank you

[Mohammad_Refaei · Accepted solution]

You could be facing an issue because of the booking date of your values. Do you work with day or month granularity?

For example, if you are working with day granularity then 24-July-2021 will be rolled back to 24-July-2020... it is not the whole month then and this is what happens with the datedd. Is this what you are looking for and you are getting wrong values?

It will help if you share a sample of your data model. 

[PBI-Curious]

m_refaei

understood, makes sense.

Thank you