Distinct count for Issue History

Hi,
I have the following configuration:
-> Columns: Measures (Issues History) ; Status (Category)
-> Pages: Project (All projects by category)
-> Rows (Time)

When I select specific components in the project filter, if an issue has 2 components, it is counted 2 times.
So instead having, for eg. 10 issues in Done, I have 11 (9 issues with one component and one issue with 2 components).
I was trying to find a formula for distinct count, but without result.

Does somebody has any suggestions how can I display the right number?
Thank you