I am not sure if I have understood your requirement correctly - if I have not, please help me understand and am happy to help if I can! ;-)
I think you need to look at defining the Partitioning & Addressing fields correctly (online help available here), and then use the "Restarting Every" option correctly to arrive at the result you are looking for. See the image attached.
Does that help?
I see what you're saying(I think), but it seems I have very few options..I only have three: Table(down), Cell, Customer Name. Choosing them only gives me replicates of Table(Down) or just the COUNTD calc (second col from right).
I'm not familiar with "Restart Every"..but it sounds promising..
I can get unique skus in combined customers by creating various Groups..but this is very tedious & not at all flexible.
I don't see an image attached..
OK..I see the attachment now. I did look into Advanced-Compute Using, but the only option I have it Customer Name & it's on the right side (it is being used..). No other options are available.
As Siraj noted, it's a matter of partitioning, however I can't think of a way to get this using normal partitioning. The issue is that in order to do the running sum of the count of distinct SKUs across the "set" of customers so far in the table, each customer "row" in the output needs to have access to all of the prior rows in the data in order to identify the unique SKUs. An alternative way of putting this is that the first row in the data needs to be checked for a unique SKU N times, where N is the number of customer rows. So we need to have access to all the data for most every row in the output. When just Customer is in the view, each Customer row can only "see" the SKUs for that customer, so the running sum won't work. Therefore, SKU needs to be in the view as well.
In the attached, there are 4 table calculations that are nested together. The latter three might be able to be optimized into fewer calcs. The calcs are:
1. Raw Count of SKU - with a Compute Using of SKU, Customer, sorted by SKU/Minimum/Ascending this generates the count of distinct SKUs.
2. Total SKU per Customer - Nested Computed Using of SKU, this identifies how many unique SKUs are for the customer.
3. Running Sum of SKU - Nested Compute Using of Customer, this generates the actually running sum of SKU. However, it returns one row per SKU, which would create overlapping text.
4. Final Running Sum of SKU - Nested Compute Using of SKU, returns only one row per customer.
Note that for you to include this in the worksheet that you attached the screenshot of, most all the other calcs will need to be modified to not return overlapping text.
Thanks Jonathan..I'll give your approach a spin and see if I can get it to work.