LTM measure issue

Hi, Nikolainoergard 

Based on your information, I create a sample table:

Then create a calculated column and try the following DAX expression:

Volume effect = [Sales_PY] * DIVIDE([Trench_Volume], [Trench_Volume_PY]) - [Sales_PY]

Create a measure:

Volume Effect LTM = 
VAR _MaxPeriod = MAX('Table'[Calendar_ConsecutiveFiscalPeriod])
VAR _MinPeriod = _MaxPeriod - 12
VAR _Result =
    CALCULATE(
        SUM('Table'[Volume effect]), 
        ALL('Table'),
            'Table'[Calendar_ConsecutiveFiscalPeriod] <= _MaxPeriod &&
            'Table'[Calendar_ConsecutiveFiscalPeriod] > _MinPeriod
    )
RETURN
    _Result

Here is my preview:

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Best Regards

Yongkang Hua

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