Day to day comparison against same period last year

[Fowmy]

I am trying to compare sales of each store with last year based on the currently selected period.  The issue here, there were no sales in this year and last year for certain days, What I am exactly looking for is to compare between dates that were available both in this year and last year.

I got the current year sales calculation working with the following formula but I cannot find a solution for the previous year sales total.

CY SALES = CALCULATE([Sales Amount],
            FILTER(CROSSJOIN(VALUES(DIM[STORE]),VALUES(CAL[DATE])),
               CALCULATE([Sales Amount],SAMEPERIODLASTYEAR(CAL[DATE]))>0
            )
           )

The amount for last year should be 261,057

https://1drv.ms/u/s!AmoScH5srsIYt0Fr8L-6r8HkFEI7

[AlbertoFerrari · Accepted solution]

Hi, this code should work. You can return CY, LY or delta (the number computed right now) by simply changing the RETURN part:

Diff = 
SUMX ( 
    SUMMARIZE ( 'FACT', 'CAL'[DATE], DIM[STORE] ),
    VAR SalesCY = [CY Sales Amount]
    VAR SalesLY = CALCULATE ( [CY Sales Amount], SAMEPERIODLASTYEAR( CAL[DATE] ) )
    RETURN
    IF ( 
        AND ( SalesCY > 0, SalesLY > 0 ),
        SalesCY - SalesLY
    )
)

It is not going to be a top-performer in terms of speed, but good enough for small data volumes.

Have fun with DAX!

Alberto Ferrari
http://www.sqlbi.com

[AlbertoFerrari · Accepted solution]

Hi, this code should work. You can return CY, LY or delta (the number computed right now) by simply changing the RETURN part:

Diff = 
SUMX ( 
    SUMMARIZE ( 'FACT', 'CAL'[DATE], DIM[STORE] ),
    VAR SalesCY = [CY Sales Amount]
    VAR SalesLY = CALCULATE ( [CY Sales Amount], SAMEPERIODLASTYEAR( CAL[DATE] ) )
    RETURN
    IF ( 
        AND ( SalesCY > 0, SalesLY > 0 ),
        SalesCY - SalesLY
    )
)

It is not going to be a top-performer in terms of speed, but good enough for small data volumes.

Have fun with DAX!

Alberto Ferrari
http://www.sqlbi.com

[Fowmy · Accepted solution]

Firstly, I should say that  It's my honor to have the question answered by Aberto Ferrari !

The solution worked perfectly, 

I was overly focusing on time intelligence and failed to make use of SUMX and variables. 

DAX is getting more interesting.

Thanks again!

[Fowmy]

I am trying to compare sales of each store with last year based on the currently selected period.  The issue here, there were no sales in this year and last year for certain days, What I am exactly looking for is to compare between dates that were available both in this year and last year.

I got the current year sales calculation working with the following formula but I cannot find a solution for the previous year sales total.

CY TEST = CALCULATE([Sales Amount],
            FILTER(CROSSJOIN(VALUES(DIM[STORE]),VALUES(CAL[DATE])),
               CALCULATE([Sales Amount],SAMEPERIODLASTYEAR(CAL[DATE]))>0
            )
           )