PowerPivot need repeat values by date

[macfuller]

I am trying to duplicate values for dates when all I have is the start date. It's a SUM of all relevant volume but not cumulative since I don't want to add from the prior month.

I receive a row value showing weekly quantity processed by start date. I also have a standard date table with every date in the range.

Customer Volume Start Date
A 20,000 5/1/2017
B 10,000 5/1/2017
A 5,000 8/1/2017
C 10,000 10/1/2017

I would like the result to be a pivot table showing the total volume for each month

	2017	2018
Jan		45,000
Feb		45,000
Mar		45,000
Apr		45,000
May	30,000	45,000
Jun	30,000	etc
Jul	30,000
Aug	35,000
Sep	35,000
Oct	45,000
Nov	45,000
Dec	45,000

<tbody>
</tbody>

How can I write a DAX measure to provide the numbers? I would also like to have other derived measures (e.g. cost per unit) based on the volume totals.

 

[macfuller]

Just to verify, the standard Cumulative pattern adds the prior month instead of duplicating it. So

Cumulative Production:=
[SIZE=1][COLOR=#008000][SIZE=1][COLOR=#008000]CALCULATE[/COLOR][/SIZE][/COLOR][/SIZE][SIZE=1] ([/SIZE]
[SIZE=1]    [Monthly Production],
[/SIZE][SIZE=1][COLOR=#008000][SIZE=1][COLOR=#008000]FILTER[/COLOR][/SIZE][/COLOR][/SIZE][SIZE=1] ([/SIZE]
[SIZE=1][COLOR=#008000][SIZE=1][COLOR=#008000]ALL[/COLOR][/SIZE][/COLOR][/SIZE][SIZE=1] ( 'Calendar'[Date] ),[/SIZE]
[SIZE=1]        'Calendar'[Date] <= 
[/SIZE][SIZE=1][COLOR=#008000][SIZE=1][COLOR=#008000]MAX[/COLOR][/SIZE][/COLOR][/SIZE][SIZE=1] ( 'Calendar'[Date] )[/SIZE]
[SIZE=1]    )
)
[/SIZE]

Would generate $30,000 in May 2017, $60,000 in June, etc.

I may have to write a macro to "spread" the initial values into a weekly or monthly set of rows for the term of the facility's production run and then import that as a table, but surely there's a simple DAX measure for this...?

 

[macfuller]

This measure does what I intended, but the nuances of having to use CALCULATETABLE are beyond me.

Monthly Forecast Pieces:=SUMX (
    CALCULATETABLE (
        tblPounds,
        FILTER (
            tblPounds,
            tblPounds[Start Date] <= MAX ( 'Calendar'[Date] )
        )
    ),
    tblPounds[Monthly Pieces]
)