how to get value in table column and use it in set analysis?

achates2008 — Fri, 23 Feb 2018 06:09:14 GMT

I have a report that will calculate by context as below.

The first Open Backlog is saved in database, then latter will be calculated as: Open Backlog + Order - Shipment = Backlog = Next Open Backlog.

Currently I am using expression as : If(RowNo(total)=1, Sum(Total Netbl),Above(TOTAL [Backlog],1))

The problem is, if I select year 2018, then I will lose the beginning backlog so the result will be wrong.

To solve this, I am thinking to calculate with a way like:

Backlog = Sum(Total Netbl) + Sum({<Week={'<current week'}>} Order) - Sum({<Week={'<current week'}>} Shipment)

So is there a way to get the value of "current week" which is presented in the column "week"?

Or is there other solution to avoid the issue?

topic how to get value in table column and use it in set analysis? in QlikView