Market Share delta calculation

[Touaibia]

Hello everyone,

I'm new in PowerBi and i want to calculate the "market share Delta" for my Dashboard. (Market share gain or loss YOY).

Soo i first started  calculating the current year MS with this mesure : 

Market Share =

DIVIDE([total_value],(CALCULATE(SUM('Sell-out Gers'[Value]),ALL('Sell-out Gers'[Level 2])

)))

And in the second step i'm supposed to calculate the Market Share for the last Year or the N-1 and i'm stuck anyone can give  me a tip on how i should write my code ? i tried "dateadd" and "sameperiodelastyear" functions but obviosly i'm doing somthing wrong.

Thanks By advance.

BR,

[daxer-almighty]

Please read this: Standard time-related calculations – DAX Patterns

To do such calculations your model needs to be a proper star-schema and have a proper Date(time) dimension.

Please read this: Understand star schema and the importance for Power BI - Power BI | Microsoft Docs

[Touaibia]

Hello and Thanks for your aswer, actually i'm receiving this data from a 3rd part vendor soo the data model is perfectly set and my time dimension is clean.

I also calculated my last year sales with this formula : 

LY_Sales = CALCULATE([total_value],SAMEPERIODLASTYEAR('Sell-out Gers'[Date].[Date]))

And it works. But for market share delta i'm still stuck 😞

BR,

[daxer-almighty]

Sorry to say that but this line:

LY_Sales = CALCULATE([total_value],SAMEPERIODLASTYEAR('Sell-out Gers'[Date].[Date]))

is a clear sign your model is WRONG. Simply wrong.

But I don't have time to explain why. There are too many articles (even on this forum) that explain why. I don't have time to repeat.