How to calculate the difference of the sum over the same column when filtered by max and min dates

[dianecrz]

I need some help building a formula in DAX. I want to calculate the amount sold between the most recent date and the oldest one. The first part of my statement is working but I am having trouble calculating the difference between dates. The numbers I see as results are close to what was expected but still don’t match exactly. I think filters may be affecting my calculations or something similar. I tried removing the KEEPFILTERS function and using FILTER instead but it also didn’t work.

Delta_Qty = VAR MAXDATE = MAX(Table1[SNAPSHOT_DATE])

VAR MINDATE = MIN(Table1[SNAPSHOT_DATE])

RETURN  IF ( HASONEVALUE (Tabl1e[DATE]),SUM(Table1[QUANTITY]), (CALCULATE (SUM(Table1[QUANTITY]), KEEPFILTERS(Table1[DATE]= MAXDATE)) - (CALCULATE (SUM(Table1[QUANTITY]), KEEPFILTERS(Table1[DATE]= MINDATE)))))

[dianecrz]

@Greg_Deckler @Anonymous @

First, thank you for your detailed answers. I apologize for posting this issue without properly documenting my problem, it was my first time publishing in the community. 

I tried the measure suggested but I am still facing one error. This is what I am using: 

Diff = 
IF (
    HASONEVALUE ( Table[Snapshot_Date] ),
    ( ( SUM(Table[Orders]) ) ),
    CALCULATE (
            ( SUM(Table[Orders])),
            FILTER (
                Table,
                Table[Snapshot_Date] = MIN ( ( Table[Snapshot_Date] ) )
            )
    ) 
        - CALCULATE (
        ( SUM(Table[Orders])),
        FILTER (
            Table,
            Table[Snapshot_Date] = MAX ( ( Table[Snapshot_Date] ) )
        )
    )
        ) ​

The screenshot below shows that my Delta works when calculating the difference for the selected dates and rows below.

However, there are cases where the measure is not working, specifically when we have 0 for the maximum date and a positive value > 0 for the minimum date. Example below:

For the highlighted row, the delta should be -0.1 instead. All other rows in this matrix are making sense. 

Can someone please help me out with this issue? 

Sincerely, 

Diane

[Anonymous · Accepted solution]

Hi @dianecrz ,

I think you can try this code to create a measure.

Delta_Qty =
VAR MAXDATE =
    MAX ( Table1[SNAPSHOT_DATE] )
VAR MINDATE =
    MIN ( Table1[SNAPSHOT_DATE] )
RETURN
    IF (
        HASONEVALUE ( Table1[SNAPSHOT_DATE] ),
        SUM ( Table1[QUANTITY] ),
        (
            CALCULATE (
                SUM ( Table1[QUANTITY] ),
                FILTER ( Table1, Table1[SNAPSHOT_DATE] = MAXDATE )
            )
                - (
                    CALCULATE (
                        SUM ( Table1[QUANTITY] ),
                        FILTER ( Table1, Table1[SNAPSHOT_DATE] = MINDATE )
                    )
                )
        )
    )

 Result is as below.

Best Regards,
Rico Zhou

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

[Greg_Deckler]

@dianecrz Sorry, having trouble following, can you post sample data as text and expected output?
Not really enough information to go on, please first check if your issue is a common issue listed here: https://community.powerbi.com/t5/Community-Blog/Before-You-Post-Read-This/ba-p/1116882

Also, please see this post regarding How to Get Your Question Answered Quickly: https://community.powerbi.com/t5/Community-Blog/How-to-Get-Your-Question-Answered-Quickly/ba-p/38490

The most important parts are:
1. Sample data as text, use the table tool in the editing bar
2. Expected output from sample data
3. Explanation in words of how to get from 1. to 2.