PreviousMonth not returning any data

[marktait]

Hi.

I'm trying to setup a simple table using the PreviousMonth function.

The two measures are setup as follows:

• Risk Score Calc = average(Defender[Risk Score - %Total])
  

• Risk Score Calc Prev = calculate([Risk Score Calc],PREVIOUSMONTH(Defender[Extract Month]))
  

My table in PBI is setup and correctly showing the "Risk Score Calc", however the "Risk Score Calc Prev" is not showing any data:

"Extract Month" is setup as a date:

Can anyone see why "Risk Score Calc Prev" is not showing any data?

Thanks for any help,

Mark

[marktait]

Thank you very much - that solved the issue.

[CoreyP · Accepted solution]

Power BI is built so that it best functions when models are in a star schema. Time intelligence functions require this, specifically a date dimension table. You need to create a date dimension table, establish a relationship to your fact table, and adjust your DAX measure to utilize the date table. 

[marktait]

Hi Corey - thank you for the suggestion.

I created a date table, which lists all days (monthly), including all dates in my "Defender (facts)" table:

I linked them as follows:

..and I changed the calculation to:

Risk Score Calc Prev = calculate([Risk Score Calc],PREVIOUSMONTH(DateListTable[Dates]))

However, the table still remains the same, with the Prev column unpopulated.

Thanks again for any help,

Mark

[CoreyP]

Date tables need to have a contiguous series of dates. ( Each row is a day, not a month. ) Use the function CALENDAR with FIRSTDATE and LAST DATE to create a dynamic date table with a contiguous set of dates.