DAX Function to create sales difference between two consecutive dates

[SC30GSWNBA]

Hello Everyone,

I am stuck in creating DAX function to create sales difference between two consecutive dates. I have a data in the following table shown below - 

As_of_Date	Sales
07-05-2025	34
07-05-2025	34
07-05-2025	34
08-05-2025	54
09-05-2025	23
09-05-2025	23
10-05-2025	56
10-05-2025	56
10-05-2025	56
10-05-2025	56
10-05-2025	56
13-05-2025	12
13-05-2025	13
13-05-2025	14
14-05-2025	23
14-05-2025	23
15-05-2025	45
16-05-2025	67
17-05-2025	89
17-05-2025	89
17-05-2025	89
17-05-2025	89
17-05-2025	89
17-05-2025	89
20-05-2025	12
20-05-2025	12
20-05-2025	12
21-05-2025	34
21-05-2025	34
22-05-2025	56
22-05-2025	56
22-05-2025	56
23-05-2025	78
24-05-2025	56
27-05-2025	98
27-05-2025	98
27-05-2025	98

I need to create a DAX measure to calculate daily total sales and a T-1 sales column to create sales difference between two consecutive days. 

Also there is no sales on weekends, so we need to take care of no sales on weekends while calculating the measure - Previous Day Sales

[Ritaf1983]

Hi @SC30GSWNBA  you can create 2 measures :

PreviousDateSales =

VAR CurrentDate = MAX('Sales table'[As_of_Date])

VAR PreviousDate = CALCULATE(MAX('Sales table'[As_of_Date]), 'Sales table'[As_of_Date] < CurrentDate)

RETURN

CALCULATE(SUM('Sales table'[Sales]), 'Sales table'[As_of_Date] = PreviousDate)

For Delta :

Delta = [sales_]-[PreviousDateSales]

Result :

PBIX is attached

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

[SC30GSWNBA]

The PreviousDate VAR is returning me 31st Dec 2024. May be that's the reason why it is not working.

[Ritaf1983]

Hi @SC30GSWNBA  i see that all results are correct....

Did you download the pbix to follow thr steps?

If yes please show what is wrong

[SC30GSWNBA]

Yes, I downloaded your file. I am connected to a database and when I apply MAX(Sales Data[Date]), it gives me 31st Dec 2024 as the output rather than the latest date. Not sure why that is happening.

[Ritaf1983]

Unfortunately, I can't determine the exact problem without access to your file.

There's an alternative method to access the value in the row above within a visualization context using the offset function.

Regrettably, I'm currently not at my computer and cannot provide an example. However, you can refer to the guide linked below:

https://youtu.be/C3QY0DWts8w?si=b5JhPQwq51lLw1tO