Sales Value Previous year from disconnect table

[Asmoday1507]

Hey,
I've been given an assignment that I completely don't know how to do correctly. I'm supposed to create a table that shows the last 12 months of sales ratio. The sales ratio is calculated as current sales to sales one year back.

With the date table connected to the data model, I calculated this as CALCULATE(SUM(Table[value]), SAMEPERIODLASTYEAR(DIM_DATE[Date])). However, in case I want to always show the last 12 months, then I have to create an additional table with dates and from it select the periods to visualize and based on that calculate the sales indicator, which completely doesn't work for me. Sameperiodlastyear doesn't work with disconnected table. 

For example, for 2024'08 it's 300M, for 2023'08 it's 380M, so how to calculate with disconnect table?

[Asmoday1507]

YearMo	DateKey	Sales in millions
01.01.2023	20230101	100
01.02.2023	20230201	300
01.03.2023	20230301	340
01.04.2023	20230401	389
01.05.2023	20230501	200
01.06.2023	20230601	400
01.07.2023	20230701	204
01.08.2023	20230801	209
01.09.2023	20230901	207
01.10.2023	20231001	390
01.11.2023	20231101	270
01.12.2023	20231201	310
01.01.2024	20240101	370
01.02.2024	20240201	380
01.03.2024	20240301	390
01.04.2024	20240401	200
01.05.2024	20240501	310
01.06.2024	20240601	370
01.07.2024	20240701	280
01.08.2024	20240801	390
01.09.2024	20240901	240

I've calendar table which is connect by DateKey with FactTable as follows.

I wanna get a table visual, where I'll have Last 12 months dynamically. So for example, if i will choose data from 2024-09 in my calendar table, then I wanna see data from 2023-09 to 2024-09. In addition I wanna get sales ratio as comparison sales in 2024 to sales in 2023. For example for 2024-09 it's 240M and for 2023-09 it's 207M, so ratio should be 240/209.

Thanks in advance

And sorry for data formatting, It gets me a lot of errors if I wanna copy data from my excel. 

[lbendlin · Accepted solution]

You can use quick measures for that

[lbendlin]

yeah, you should not need a disconnected table in that scenario. You do need a calendar table though (which you seem to have).

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