Running calculations

[rileybloke]

Hi,
I have powerpivot model that includes 4 tables of data.

1. Product Item Key table

• Item Number
• Stock on hand (now)

2. Date Key Table

• Year
• Week Number

3. Customer Order Table

• Item Number
• Year
• Week
• Order Quantity

4. Supplier Delieries Table

• Item Number
• Year
• Week
• Delivery Quantity

I need help with a dax calculation or measure to sum the order quantities for each item for each year/week, and the same for supplier deliveries.
And then present it on a Pivot table running across years/weeks, but as a running calculation starting from the STOCK OH(table1), and deducting by customer order, and adding supplier orders, this will then show if any items will become out of stock.

Ive attached what I have already done, but I need to insert another column showing the running total using the running calculation above.
Any advise or help would be great, ive been battling with it for ages, reading forums, watching youtube vids etc.

 

[rileybloke]

I have applied the same measure to the supplier delivery, and can calculate between measures. I am looking at Javiers running totals formula, but cant see how I could introduce the starting inventory figure (ACTUAL OH) into the formula to create a running calculation across the weeks Sorry I ran a ground again. In every calculation or measure I attempt it errors that Actual OH from ITEM_KEY is out of context. Probably something fundemental.