Previous Month DAX Calculation

[bmk]

I seem to be running into a road block and I think this may be straightforward. If someone can please help. 

I am using a table visual on PBI, with a bunch of measures. I have a date table. I wish to calculate a DAX filter formula on the date table to give me dates of the previous month relative to today. Assuming today's date is January 2024, I want all calculations and measures only from Dec 2023. The date table i'm using is : 

Date Table =

ADDCOLUMNS (

    CALENDAR (

        DATE ( YEAR ( today() -9999), MONTH ( today() - 9999), DAY ( today()- 9999) ),

        DATE ( YEAR ( today() ), MONTH ( today() ), DAY ( today() ) )

    ),

    "DateAsInteger", FORMAT ( [Date], "YYYYMMDD" ),

    "Year", YEAR ( [Date] ),

    "Monthnumber", FORMAT ( [Date], "MM" ),

    "YearMonthnumber", FORMAT ( [Date], "YYYY/MM" ),

    "YearMonthShort", FORMAT ( [Date], "YYYY/mmm" ),

    "MonthNameShort", FORMAT ( [Date], "mmm" ),

    "MonthNameLong", FORMAT ( [Date], "mmmm" ),

    "DayOfWeekNumber", WEEKDAY ( [Date] ),

    "DayOfWeek", FORMAT ( [Date], "dddd" ),

    "DayOfWeekShort", FORMAT ( [Date], "ddd" ),

    "Quarter", "Q" & FORMAT ( [Date], "Q" ),

    "YearQuarter", FORMAT ( [Date], "YYYY" ) & "/Q"

        & FORMAT ( [Date], "Q" ),

    "Start of Week",[Date]  - WEEKDAY([Date],2) +1,

    "Week Ending",[Date] + 7 - WEEKDAY([DATE],2),

    "Week Range",[Date]  - WEEKDAY([Date],2) +1&" - "&[Date] + 7 - WEEKDAY([DATE],2),

    "MonthYear", FORMAT ( [Date], "mmmm" )&"/"&YEAR ( [Date] ),

    "WeekNum",weeknum([Date],2)-1

)

and the DAX I tried is :

IsPreviousMonth =

    IF(

        'Date Table'[Date] >= STARTOFMONTH('Date Table'[TodayDate])

        && 'Date Table'[Date] < STARTOFMONTH('Date Table'[TodayDate]) - 1,

        1,

        0

    )

[bmk]

Thank you, Adam.

[v-kongfanf-msft]

Hi @bmk ,

I've changed your code., you can try below dax:

Date Table = 
ADDCOLUMNS (
CALENDAR (
DATE ( YEAR ( today() ) - 10 ,1 ,1 ),
DATE ( YEAR ( today() ),12 ,31 )),
"DateAsInteger", FORMAT ( [Date], "YYYYMMDD" ),
"Year", YEAR ( [Date] ),
"Monthnumber", FORMAT ( [Date], "MM" ),
"YearMonthnumber", FORMAT ( [Date], "YYYY/MM" ),
"YearMonthShort", FORMAT ( [Date], "YYYY/mmm" ),
"MonthNameShort", FORMAT ( [Date], "mmm" ),
"MonthNameLong", FORMAT ( [Date], "mmmm" ),
"DayOfWeekNumber", WEEKDAY ( [Date] ),
"DayOfWeek", FORMAT ( [Date], "dddd" ),
"DayOfWeekShort", FORMAT ( [Date], "ddd" ),
"Quarter", "Q" & FORMAT ( [Date], "Q" ),
"YearQuarter", FORMAT ( [Date], "YYYY" ) & "/Q"
& FORMAT ( [Date], "Q" ),
"Start of Week",[Date] - WEEKDAY([Date],2) +1,
"Week Ending",[Date] + 7 - WEEKDAY([DATE],2),
"Week Range",[Date] - WEEKDAY([Date],2) +1&" - "&[Date] + 7 - WEEKDAY([DATE],2),
"MonthYear", FORMAT ( [Date], "mmmm" )&"/"&YEAR ( [Date] ),
"WeekNum",weeknum([Date],2)-1
)

Best Regards,
Adamk Kong

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

[Fowmy · Accepted solution]

@bmk 

Add calculated column as follows:

Previous Month = INT('Date Table'[Date] IN CALENDAR( EOMONTH( TODAY() , -2)+1 , EOMONTH( TODAY() , -1) ))

I suggest you modify your calender table date range as follows, not to have too many dates/rows. I entere 10 years back so you can chagne it in terms of years:

ADDCOLUMNS (
CALENDAR (
DATE ( YEAR ( today() ) - 10 ) ,1 ,1 ),
DATE ( YEAR ( today() ),12 ,31 ),

[bmk]

Fowmy, the calculated column worked great, thank you. I did try to modify the Date DAX overall as per your suggestion, but I am getting a DAX syntax error. Can you please check what I am missing.


Date Table =
ADDCOLUMNS (
CALENDAR (
DATE ( YEAR ( today() ) - 10 ) ,1 ,1 ),
DATE ( YEAR ( today() ),12 ,31 ),
),
"DateAsInteger", FORMAT ( [Date], "YYYYMMDD" ),
"Year", YEAR ( [Date] ),
"Monthnumber", FORMAT ( [Date], "MM" ),
"YearMonthnumber", FORMAT ( [Date], "YYYY/MM" ),
"YearMonthShort", FORMAT ( [Date], "YYYY/mmm" ),
"MonthNameShort", FORMAT ( [Date], "mmm" ),
"MonthNameLong", FORMAT ( [Date], "mmmm" ),
"DayOfWeekNumber", WEEKDAY ( [Date] ),
"DayOfWeek", FORMAT ( [Date], "dddd" ),
"DayOfWeekShort", FORMAT ( [Date], "ddd" ),
"Quarter", "Q" & FORMAT ( [Date], "Q" ),
"YearQuarter", FORMAT ( [Date], "YYYY" ) & "/Q"
& FORMAT ( [Date], "Q" ),
"Start of Week",[Date] - WEEKDAY([Date],2) +1,
"Week Ending",[Date] + 7 - WEEKDAY([DATE],2),
"Week Range",[Date] - WEEKDAY([Date],2) +1&" - "&[Date] + 7 - WEEKDAY([DATE],2),
"MonthYear", FORMAT ( [Date], "mmmm" )&"/"&YEAR ( [Date] ),
"WeekNum",weeknum([Date],2)-1
)

[Fowmy]

@bmk 

I fixed it, please try now.

Date Table = 
ADDCOLUMNS (
CALENDAR (
    DATE ( YEAR ( today() ) - 10  ,1 ,1 ),
    DATE ( YEAR ( today() ), 12 ,31 )
),
"DateAsInteger", FORMAT ( [Date], "YYYYMMDD" ),
"Year", YEAR ( [Date] ),
"Monthnumber", FORMAT ( [Date], "MM" ),
"YearMonthnumber", FORMAT ( [Date], "YYYY/MM" ),
"YearMonthShort", FORMAT ( [Date], "YYYY/mmm" ),
"MonthNameShort", FORMAT ( [Date], "mmm" ),
"MonthNameLong", FORMAT ( [Date], "mmmm" ),
"DayOfWeekNumber", WEEKDAY ( [Date] ),
"DayOfWeek", FORMAT ( [Date], "dddd" ),
"DayOfWeekShort", FORMAT ( [Date], "ddd" ),
"Quarter", "Q" & FORMAT ( [Date], "Q" ),
"YearQuarter", FORMAT ( [Date], "YYYY" ) & "/Q"
& FORMAT ( [Date], "Q" ),
"Start of Week",[Date] - WEEKDAY([Date],2) +1,
"Week Ending",[Date] + 7 - WEEKDAY([DATE],2),
"Week Range",[Date] - WEEKDAY([Date],2) +1&" - "&[Date] + 7 - WEEKDAY([DATE],2),
"MonthYear", FORMAT ( [Date], "mmmm" )&"/"&YEAR ( [Date] ),
"WeekNum",weeknum([Date],2)-1
)

[bmk]

Thank you, Fowmy.

[talespin]

Hello,

This returns a table with all dates(datetime) from previous month. Please replace first parameter with your calendar table.

DATESBETWEEN( 'Calendar'[MasterDate], EOMONTH(TODAY(), -2) + 1 , EOMONTH(TODAY(), -1))