Create new calculated member for issues not fixed in version

Hello,

for Bugs we put AffectsVersion and FixVersion fields. It happens that a bugA is been reported during development on AffectsVersion 1.2.0 (unreleased) and later is been fixed for the same FixVersion 1.2.0 (which is later being officially released). For another bugB which is also been reported on AffectsVersion 1.2.0 during development we are have fixed it only in a later version 1.3.1.
Both the bugs have been closed by today (BugA already in 1,2.0 version and BugB in 1.3.1 version).

We consider a bug with AffectsVersion = FixVersion and status = closed as fixed for the given version, even you may argue it is not, because we have this version still in the AffectsVersion field. But that’s the convention we use.

Now I would like to create a table showing all (known) bugs on a given Version (here 1.2.0 for example). I put Affects Versions as Page and Issues and Priority in Rows. As measure I can easily use Open Issues and Created Issues.
This shows me a table as expect. Open Issues does of course only show the issues still open by today (here zero). Created Issues does show me all the tickets affecting this version (here 2).
I would like to see all open issues for this Affects Version (BugA).
I would like to have a new column which does show me all created issues (for selected affects Version (Pages)) not having the same FixVersion, let’s call them “Known issues”.

How can I achieve this?
Many thanks in advance
Christian