Total difference between current and previous date

HI Anonymous ,

You can try to use the following measure formulas if they suitable for your requirements:

Total closed = 
CALCULATE (
    COUNT ( T1[TaskID] ),
    FILTER ( ALLSELECTED ( T1 ), [SnapshotDate] <= MAX ( T1[SnapshotDate] ) )
)

Previous Closed = 
VAR currDate =
    MAX ( T1[SnapshotDate] )
VAR prevDate =
    CALCULATE (
        MAX ( T1[SnapshotDate] ),
        FILTER ( ALLSELECTED ( T1 ), [SnapshotDate] < currDate )
    )
RETURN
    IF (
        prevDate <> BLANK (),
        CALCULATE (
            COUNT ( T1[TaskID] ),
            FILTER (
                ALLSELECTED ( T1 ),
                [SnapshotDate] <= currDate
                    && [SnapshotDate] > prevDate
            )
        )
    )

Last Closed =
VAR currDate =
    MAX ( T1[SnapshotDate] )
VAR _lastDate =
    CALCULATE ( MAX ( T1[SnapshotDate] ), ALLSELECTED ( T1 ) )
RETURN
    IF (
        currDate = _lastDate,
        CALCULATE ( COUNT ( T1[TaskID] ), VALUES ( T1[SnapshotDate] ) )
    )

Regards,

Xiaoxin Sheng