Check if column has same value for all dates

Hi RMarston create a measure to sum the shipments for the closed months, current month and rolling calculation as follows ,use the rolling r3 measure in your visualization.

Measure_ClosedShipments =
CALCULATE(
SUM([Case Shipments 9L]),
FILTER(
'Date',
'Date'[ShipMoClosed] = "Closed"
)
)

then create another measure for calculation when the month is not fully closed 

Measure_CurrentMonthCalculation =
IF (
COUNTROWS (
FILTER (
CALENDAR ( STARTOFMONTH ( 'Date'[Date] ), ENDOFMONTH ( 'Date'[Date] ) ),
WEEKDAY ( [Date], 2 ) < 6
&& [Date]
<= MAX ( ShipmentsDataThru[Shipment Through] ) - 1
)
) > 7,
ROUND (
(
SUM ( [Case Shipments 9L] )
/ COUNTROWS (
FILTER (
CALENDAR ( STARTOFMONTH ( 'Date'[Date] ), ENDOFMONTH ( 'Date'[Date] ) ),
WEEKDAY ( [Date], 2 ) < 6
&& [Date]
<= MAX ( ShipmentsDataThru[Shipment Through] ) - 1
)
)
)
* COUNTROWS (
FILTER (
CALENDAR ( STARTOFMONTH ( 'Date'[Date] ), ENDOFMONTH ( 'Date'[Date] ) ),
WEEKDAY ( [Date], 2 ) < 6
)
),
0
),
SUM([Case Shipments 9L])
)

Create final measure for rolling 3 months sum calculation

Measure_R3 =
VAR CurrentMonth = MAX('Date'[Date])
VAR TwoMonthsAgo = EOMONTH(CurrentMonth, -2)

VAR ClosedMonthsSum =
CALCULATE(
[Measure_ClosedShipments],
DATESBETWEEN('Date'[Date], TwoMonthsAgo, EOMONTH(CurrentMonth, -1))
)

VAR CurrentMonthSum =
CALCULATE(
[Measure_CurrentMonthCalculation],
FILTER(
'Date',
'Date'[ShipMoClosed] <> "Closed"
&& MONTH('Date'[Date]) = MONTH(CurrentMonth)
&& YEAR('Date'[Date]) = YEAR(CurrentMonth)
)
)

RETURN
ClosedMonthsSum + CurrentMonthSum

use the above R3 measure in your matrix visual, this correctly sums the actual and previous closed months values.

Check and let know.

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