Help please - datesinperiod question

[Anonymous]

Hi,

I have this formula:

Test = CALCULATE(average(Rental_Net), DATESINPERIOD('Date'[Date], max('Date'[Date]),-12,MONTH))

I want to be able to change the constant 12 to a formula depending on the date I selected on the date slicer from calendar table. The problem is when I select 9 calendar months for example:

it still gets the average for the last 12 because of the constant 12. Is there a way to "macro" the 12? Thanks! 

[amitchandak · Accepted solution]

@Anonymous , if you selecting a date range from the slicer and you need that much data. you do not need datesinperiod

CALCULATE(average(Rental_Net)) , should do if date table is joined.

If you want a dynamic number in place of 12, use what if parameter  https://docs.microsoft.com/en-us/power-bi/desktop-what-if