Sum of last n days in DAX (measure)

[PBNikr]

Hey!

I am new to Power BI and struggling to get this DAX code to show me the correct values. I would like to view the following as aggregated numbers (separate cards). Note that I am using a live connection to a cube:

- Users from start

- Users last 30 days

- Users last 7 days

- Users previous day

The code that I have for Users from start is the following:

Users from start = 
    CALCULATE (
        'Users'[Amount];
        ALL('Date'[Date]))

I have tried to retrieve the users from the last 30 days, but I'm pretty sure there is a better way of doing this:

Users 30 days = 
CALCULATE (
    SUM ( 'Users'[AmountUsers] );
    FILTER (
        ALL ( 'Date'[Date] );
        'Date'[Date]
            >= MAX (  'Date'[Date] ) - 30
            &&  'Date'[Date] <= MAX (  'Date'[Date] )
    )
)

Any idea on how I can retrieve the correct data for the different n-days with a good DAX code? 

Also:

Something I noticed is that when I use the SUM() function I can't use the same fields in the calculation that are in the Users table. It looks like it can only handle hidden values. Any explanation as to why this is?

Thanks!

[Greg_Deckler]

Actually, I don't think your DAX code is half-bad considering you are connected to live to a cube. I'm not sure why you have that && clause in there as I can't think of under what circumstance would ever have a date in your cube that would somehow be greater than the max date in the cube, so it's kind of unnecessary. You could also potentially use TODAY() - 30 instead of MAX() - 30 but overall you have the right idea. 

[PBNikr · Accepted solution]

@Greg_Deckler Your right, thanks! This worked for me:

Users 30 days = 
CALCULATE (
    SUM ( 'Users'[AmountUsers] );
    FILTER (
        ALL ( 'Date'[Date] );
        'Date'[Date]
            > TODAY() - 30
    )

I couldn't figure out why I was receiving blank values but it looks like the most recent data hasn't been loaded into the test cube. Problem solved!