Transformation : Last Month Flag

What exactly you are trying to achieve? If you are trying to calculate some values based on last month you can do it by using TimeIntelligence functions.

https://docs.microsoft.com/en-us/dax/time-intelligence-functions-dax

Anonymous , In case you need a column with last month value to take a call use a formula like

countx(filter(Table, table[User] =earlier(table[User] ) && eomonth(table[date],0) =eomonth(earlier(table[date]),-1)),table[S.NO])

For a Measure : https://medium.com/@amitchandak.1978/power-bi-mtd-questions-time-intelligence-3-5-64b0b4a4090e

Hi Anonymous ,

Do you want to add a column to distinguish the last month and current month?

If yes, you can refer the following formula.

Flag = 
var _current_month = MONTH(TODAY())
var _month = MONTH('Table'[Date])
return
IF(
    _month=_current_month,
    "Y",
    IF(
        _month=_current_month-1,
        "N","Other"
        )
    )

If it doesn’t meet your requirement, could you please show the exact expected result based on the table that you have shared?

Best regards,

Community Support Team _ zhenbw

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.

BTW, pbix as attached.