The define definition could give you more links than required for this report. I would suggest importing either linked stories or linked requirements.
For example, if on Requirement issue you see links with the name Requirements Derivation (case sensitive link name, check direction as well) with a link to User stories, you can import linked user stories with this definition:
name = "Requirements_Derivation"
outward_link = "Requirements Derivation"
multiple_values = true
issue_type = "User Story"
dimension = true
Please note. If you are updating a definition of already imported custom field you would like to run full data re-import in your account in order to reimport the correct set on links based on new criteria.
Then you can use Issue dimension in the report to represent all Requirements (use Issue type on Pages to filter by Requirement).
You should see linked user stories in measure Issue Requirements_Derivation.
If you would like to count linked user stories, you would need to use some custom calculations. Here is one example:
[Issue].CurrentMember.Level.Name = "Issue"
[Requirements_Derivation].Currentmember is [Requirements_Derivation].Defaultmember
-- retrieve Requirements_Derivation information from Issue property Bugs
-- total calculation for any issue, data on Requirements_Derivation level
-- counts how many times Requirements_Derivation are reference with issues, this works as a filter as well
We have our Demo training account with some additional example formulas and reports on linked issues.
In this demo account, we have Story issues and they have linked Bugs. Reports and calculations work on this dimension and property Bugs. If you would like to reuse any of those reports or formulas, please replace Bugs with your linked dimension name (in your case with Requirements_Derivation). The example formula above is based on measure Linked bugs from this demo training account.
Daina / email@example.com