Problems WIth Total Calculating Wrong

[borelza2106]

For a table I am creating, I am trying to do a month over month calculation where we displace just the difference between Month 1 and Month 2. I have the measure working correctly but the total is wrong. The measure is including the blank value that I implemented into it, as I know the measure does, but the issue is everything I have tried to not include this blank has failed. Was wondering if anyone could teach me something I clearly don't know how to accomplish here.

Initial Calculation:

Water Consumption Difference =

IF(CALCULATE( [Total Consumption], PARALLELPERIOD(uvw_tcUtilityReading[UtilityEndDate],-1,MONTH)) = BLANK(),BLANK(),

CALCULATE( [Total Consumption], PARALLELPERIOD(uvw_tcUtilityReading[UtilityEndDate],-1,MONTH)) - [Total Consumption])

I then tried to wrap it in a SUMX and a SUMX(VALUE but if I include the whole formula I get a Blank for both regardless if I do 

Wrapping in a SUMX:

Water Consumption Difference =

SUMX(uvw_tcUtilityReading,
IF(CALCULATE( [Total Consumption], PARALLELPERIOD(uvw_tcUtilityReading[UtilityEndDate],-1,MONTH)) = BLANK(),BLANK(),

CALCULATE( [Total Consumption], PARALLELPERIOD(uvw_tcUtilityReading[UtilityEndDate],-1,MONTH)) - [Total Consumption]))

Wrapping in a SUMX(Values

[PaulDBrown · Accepted solution]

It's hard to see without sample data, but you could try the following:

Water Consumption Difference Totals =
SUMX (
    ADDCOLUMNS (
        SUMMARIZE (
            uvw_tcUtilityReading,
            uvw_tcUtilityReading[AccountName],
            uvw_tcUtilityReading[UtilityEndDate],
            uvw_tcUtilityReading[UoM]
        ),
        "DiffTotal",
            IF (
                ISBLANK (
                    CALCULATE (
                        [Total Consumption],
                        PARALLELPERIOD ( uvw_tcUtilityReading[UtilityEndDate], -1, MONTH )
                    )
                ),
                BLANK (),
                CALCULATE (
                    [Total Consumption],
                    PARALLELPERIOD ( uvw_tcUtilityReading[UtilityEndDate], -1, MONTH )
                ) - [Total Consumption]
            )
    ),
    [DiffTotal]
)

[borelza2106]

That worked to perfection! Thank you so much, this was driving me up the wall and now I can finally put it to rest!

[PaulDBrown]

Glad it worked. Just a quick Recommendation: for Time Intelligence functions (PARALLELPERIOD etc) you should be using a Date Table as a dimension table, or you might find unexpected results. 

[borelza2106]

So just create a date table, connect them, and then update the formula above to be as shown below? 

[PaulDBrown]

Exactly! Just make sure the field in the matrix is the Date [Date] field instead of the field from the main table

(The date table should contain continuous dates covering the range of dates in the model)

Edit: once you've created the date table, mark it as such using the option in the ribbon