Cumulative Formula by date

Hi, AivaS 
 Thank you for your prompt response.

1.You can try the following measure:

Measure = 
VAR table1 =
    SUMMARIZE(
        ALLSELECTED('summary_by_month'),
        'summary_by_month'[Date].[Month],
        "AVG",
        VAR cm = 'summary_by_month'[Date].[Month]
        VAR _averageProfit =
            CALCULATE(
                AVERAGE(summary_by_month[profit]),
                FILTER(
                    ALL(summary_by_month),
                    'summary_by_month'[Date].[Month] = cm
                )
            )
        RETURN _averageProfit,
        "INEDX1",
        SWITCH(
            'summary_by_month'[Date].[Month],
            "January", 1,
            "February", 2,
            "March", 3,
            "April", 4,
            "May", 5,
            "June", 6,
            "July", 7,
            "August", 8,
            "September", 9,
            "October", 10,
            "November", 11,
            "December", 12
        )
    )
 
VAR table2 =
    SUMMARIZE(
        table1,
        'summary_by_month'[Date].[Month],
        [INEDX1],
        "running",
        SUMX(
            FILTER(table1, [INEDX1] <= EARLIER([INEDX1])),
            [AVG]
        )
    )
 
VAR f =
    SUMX(
        FILTER(table1, [INEDX1] = MAX([INEDX1])),
        [AVG]
    )
 
VAR f1 =
    SUMX(
        FILTER(table2, 'summary_by_month'[Date].[Month] = MAX('summary_by_month'[Date].[Month])),
        [running]
    )
 
RETURN
    IF(
        ISINSCOPE('summary_by_month'[Date].[Month]),
        f1,
        f
    )

2.Here's my final result, which I hope meets your requirements.

Please find the attached pbix relevant to the case.

Best Regards,

Leroy Lu

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