Current vs Previous Quarter in a transition year

[n5722]

Hello,

I made a custom measure that compares the current quarter to the previous quarter based on my selection on the bar chart. Meaning if I select Q2 2021 it will calculate the difference % vs Q1 2021.

The problem that I am facing now is that when I select Q1 2021 it does not compare it to Q4 2020 (see pic below).

Here is the DAX code of my custom measure:

Here is the plane code:

TotalSalesDiff% (selected vs prev quarter) = 
VAR SelectedQ = 
    SELECTEDVALUE('Date helper (create date)'[Date].[QuarterNo])
VAR SelectedYear = SELECTEDVALUE('Date helper (create date)'[Year])
VAR TotalSalesSelectedQ = 
    CALCULATE([TotalSales], FILTER(ALL('Date helper (create date)'), 'Date helper (create date)'[Year] = SelectedYear
     && 'Date helper (create date)'[Date].[QuarterNo] = SelectedQ))
VAR TotalSalesPrevQ = 
    CALCULATE([TotalSales], FILTER(ALL('Date helper (create date)'), 'Date helper (create date)'[Year] = SelectedYear
     && 'Date helper (create date)'[Date].[QuarterNo] = SelectedQ - 1))

RETURN
DIVIDE((TotalSalesSelectedQ-TotalSalesPrevQ),TotalSalesSelectedQ,0)+0

Side note: I use a date helper table that calculates relative time (weeks, months, years etc.)

Could someone tell me how to improve my measure so that I can get the expected result? Thanks!

[amitchandak]

@n5722 , if you have dates, You can use time intelligence

QTD Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESQTD(('Date'[Date])))
Last QTD Sales = CALCULATE(SUM(Sales[Sales Amount]),DATESQTD(dateadd('Date'[Date],-1,QUARTER)))

if you do not have , You need to a separate table for Qtr Year (a date table at the higher level  )

Create a rank column on Qtr start date or Year Qtr YYYYQ

Qtr Rank = RANKX(all('Date'),'Date'[Year Qtr],,ASC,Dense)

then create measures like
This Qtr = CALCULATE(sum('Table'[Qty]), FILTER(ALL('Date'),'Date'[Qtr Rank]=max('Date'[Qtr Rank])))
Last Qtr = CALCULATE(sum('Table'[Qty]), FILTER(ALL('Date'),'Date'[Qtr Rank]=max('Date'[Qtr Rank])-1))

Power BI — Qtr on Qtr with or Without Time Intelligence
https://medium.com/@amitchandak.1978/power-bi-qtd-questions-time-intelligence-2-5-d842063da839
https://www.youtube.com/watch?v=8-TlVx7P0A0

[n5722]

Hi @amitchandak . Thank you for your reply but this does not fix my problem. I am not trying to calculate QTD sales, I am trying to calculate the difference between the currently selected month and the month before it.

My measure works great if the calculation is taking place within the year but when I select Q1 2021 it does not calculate the difference vs Q4 of 2020 as it stays in the context of 2021.