TL;DR underlined and bold Hi all, I am attempting to create an area chart visual to show the production plan of a given product my company makes so that my staff can see stock issues on the horizon and raise purchase orders.
Ideally I would have a cumulative area chart showing three key things cumulative Forecasts[Forecast.Volume] by month, cumulative Sales[Sale.Volume] by month, and finally cumulative planned stock build by month (more on that later).
Here is what I currently have set up:
The relationships between forecasts and sales are working perfectly (using a date table and a product table). What I am missing (apart from a bunch of sales in Jan and Feb 
) is the cumulative behaiviour, and my research hasn't really brought me any closer to creating that.
The second thing missing is cumulative planned stockbuild. Planned Stockbuild of a product consists of Stocks[Stock.InStock] filtered by Stocks[Stock.AsAtDate]=Today (AsAt Dates are related to a seperate date table due to the different nature of them - anyway I don't have issues with this part) together with Purchases[Purchase.Quantity] which are flowing in to the warehous at Purchases[Purchase.Date]. This should be a fairly simple calculation - I really need to become more fluent in DAX because I should really be able to do this (I ordered a few books from amazon which will arrive soon!).
Thanks in advance for any advice from DAX experts out there!