Unique timeline from the overlapping time stamp

Hi, Anonymous 

Based on your description, I created data to reproduce your scenario. The pbix file is attached in the end.

Table:

You may create a measure as below.

Result Measure = 
SUMX(
    SUMMARIZE(
        'Table',
        'Table'[Employee],
        "Result",
        CALCULATE(
            SUM('Table'[Difference]),
            FILTER(
                'Table',
                MONTH([Start Time])=2&&
                DAY([Start Time])=4
            )
        )
    ),
    [Result]
)

Result:

Or you can create the following calculated table.

Table 2 = 
SUMMARIZE(
        'Table',
        'Table'[Employee],
        "Result",
        CALCULATE(
            SUM('Table'[Difference]),
            FILTER(
                'Table',
                MONTH([Start Time])=2&&
                DAY([Start Time])=4
            )
        )
)

Result:

Best Regards

Allan

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