Average Volume Week YTD by Store

Hi, kbarc24 

Based on your information, I create a sample table:

Then create measures and try the following DAX expression:

Rolling Average Volume A = 
VAR CurrentWeek = MAX('Table'[Week])
RETURN
AVERAGEX(
    FILTER(
        ALL('Table'),
        'Table'[Week] <= CurrentWeek && 'Table'[Store A] <> BLANK()
    ),
    'Table'[Store A]
)

Rolling Average Volume B = 
VAR CurrentWeek = MAX('Table'[Week])
RETURN
AVERAGEX(
    FILTER(
        ALL('Table'),
        'Table'[Week] <= CurrentWeek && 'Table'[Store B] <> BLANK()
    ),
    'Table'[Store B]
)

Rolling Average Volume C = 
VAR CurrentWeek = MAX('Table'[Week])
RETURN
AVERAGEX(
    FILTER(
        ALL('Table'),
        'Table'[Week] <= CurrentWeek && 'Table'[Store C] <> BLANK()
    ),
    'Table'[Store C]
)

Here is my preview:

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Best Regards

Yongkang Hua

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