Calculate difference between two periods while selecting one period from slicer

[relliott]

This question is similar to others, but I couldn't find any posts solving for the unique challenge I'm having. 

I have a simple sales table with Rep, Quarter, and Sales. I want the report user to be able to select a quarter via a filter and then see the difference in sales versus the prior quarter. I have a measure that is calculating the differences fine using SWITCH, however if a rep is not present in the quarter selected, they do not show up in the output. Below I am showing small set of sample data, the expected output, and the output I am getting along with the measure i created to calculate the delta. Can someone please help me solve to make sure all line items show up? 

Measure to calculate difference: 

Delta =

SWITCH(

SELECTEDVALUE(Sales[Quarter]),

"Q2", BLANK(),

"Q3", CALCULATE(SUM(Sales[Sales]),Sales[Quarter]="Q3")-CALCULATE(SUM(Sales[Sales]),Sales[Quarter]="Q2"),

BLANK()

)

Sales Table Sample Data

Desired Output when user selects Q3 from slicer

Actual Output I'm seeing where Joe does not show up:

[v-henryk-mstf · Accepted solution]

Hi @relliott ,

Try the following calculated column and measure:

Q_ = IF(Sales[Quarter]="Q2",0,1)

M1 = 
VAR A =
    CALCULATE (
        MIN ( Sales[Sales] ),
        FILTER ( ALL ( Sales ), MAX ( Sales[Q_] ) = 0 )
    )
VAR B =
    CALCULATE (
        MAX ( Sales[Sales] ),
        FILTER ( ALL ( Sales ), MAX ( Sales[Q_] ) = 1 )
    )
RETURN
    CALCULATE ( B - A, FILTER ( ALL ( Sales ), MAX ( Sales[Rep] ) = Sales[Rep] ) )

If the problem is still not resolved, please provide detailed error information and let me know immediately. Looking forward to your reply.

Best Regards,
Henry

If this post helps, then please consider Accept it as the solution to help the other members find it more quickly.