DATEDIFF from Filter

[Sportily]

Hi PowerPeople!

Please go easy, I'm a relative newbie, pushing boundaries and learning fast!

I have a working PowerBI instance. 

I am looking to add a measure which can present on a card.

The page has a Date Filter, from-to.

The calculation for the measure I need is:

Number of DAYS between the 2 dates specificied in the filter.

Divided by the total figure from column 2 in the displayed table.

Multiplied by 7

The intention is that this creates an 'Average sessions per week' figure.

IF I use 'AVERAGE', then the result is the total from column 2, divided by the number of w/c lines displyed. 

So for Feb 2021, that would be 70 divided by 5 to give an average of 14.

BUT there are only 28 days in Feb, so I really want to divide by 28*7, to give a more accurate average figure for the month = 17.5.

Screenshot attached. 

My stumbling block has been working out how to DATEDIFF reference the dates in the filter.

Thanks for all your help.

Chris

[Sportily]

Brilliant, thats ace. Thank you so much. Worked a treat. Thanks for being so helpful.

[tamerj1 · Accepted solution]

Hi @Sportily 

If the date slicer is coming from a date table then

Number of Days =

COUNTROWS ( 'Date' )

If date table is not available then create a virtual one and count its rows

Number of Days =

COUNTROWS(

CALENDAR(MIN(Table[Date]), MAX(Table[Date]))

)