Measure: Getting running total from previous week number

[crln-blue]

Hello! 

I have a measure that is a working running total for every week number and I also have another measure where it would display the last month's running total:

Ending Cash is the working running total for every week number. And Beginning Cash should display the last month's Ending Cash. However, I can't display it and I think my computation is wrong.  Below is the expected output:

Hierarchy	1	2	3	4
Beginning Cash	481975	526139.24	700059.27	512847.74
Ending Cash	526139.24	700059.27	512847.74	438.015.67

Data is sensitive and a lot of computations so I can't share it. Unfortunately, there is no week function on the DATEADD function. 

My column axis:

Week # = WEEKNUM(B[Date].[Date],1)

My ending cash calculated measure (running total):

Ending Cash Weekly = (SUMX(FILTER(ALLSELECTED('B'[Week #]),'B'[Week #] <= MAX('B'[Week #])),[Net Cash Flow Weekly])) + 'Query - Parameter'[Past Year End Cash Value]

My beginning cash calculated measure (the one I have problems with):

Beginning Cash Weekly = 
IF(SELECTEDVALUE('B'[Week #]) = 1,
    [Past Year End Cash Value],
    CALCULATE([Ending Cash Weekly], FILTER('B', 'B'[Week #] = SELECTEDVALUE('B'[Week #]) - 1)
    )
)

My question is, how do I compute for the Beginning Cash which takes the last period's running total? Thanks for the help!

[amitchandak]

@crln-blue , You want running total till last month ? of same week on week ?

This is till date

Cumm Sales = CALCULATE(SUM(Table[value]),filter(allselected(Table),Table[Date] <=max(Table[Date])))

Cumm Sales till last month = CALCULATE(SUM(Table[value]),filter(allselected(Table),Table[Date] <=max(dateadd(Table[Date],-1,month))))

//with date table

Cumm Sales = CALCULATE(SUM(Sales[Sales Amount]),filter(allselected(date),date[date] <=maxx(date,dateadd(date[date]),-1,month)))

[amitchandak]

@crln-blue , if you have date try like this for running total no need to week calculation, it can be part of date table

example

Cumm Sales = CALCULATE(SUM(Table[value]),filter(allselected(Table),Table[Date] <=max(Table[Date])))

Rest of the calculation is not clear to me

[crln-blue]

Hello @amitchandak , thanks for the suggestion! However, my cummulative total is working okay now. I need to use it on week num since my column axis is week num.

Edited the post, I noticed that it's a bit unclear. My problem is how do I get the last month's running total. Thanks!