DAX command for count records within a time range

Hi nhutruong ,

I suggest you to try this code to create a measure.

Appearance in Past 6 month =
CALCULATE (
    COUNT ( 'MasterTable'[Item] ),
    FILTER (
        'MasterTable',
        'MasterTable'[Item] = MAX ( 'Table1'[Item] )
            && 'MasterTable'[Timestamp] >= MAX ( 'Table1'[Start Count Date] )
            && 'MasterTable'[Timestamp] <= MAX ( 'Table1'[Week Start Date] )
    )
)

Or calculated column:

Appearance in Past 6 month =
CALCULATE (
    COUNT ( 'MasterTable'[Item] ),
    FILTER (
        'MasterTable',
        'MasterTable'[Item] = EARLIER ( 'Table1'[Item] )
            && 'MasterTable'[Timestamp] >= EARLIER ( 'Table1'[Start Count Date] )
            && 'MasterTable'[Timestamp] <= EARLIER ( 'Table1'[Week Start Date] )
    )
)

Best Regards,
Rico Zhou

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