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Hi everyone. I think the pictures can clarify better than words what my problem is. Why doesn't sums per row work? How can I fix the problem? Furthermore,
there is a way to insert the thousands separator (dot nor comma)? Thanks

Hi,
why didn't you answer the questions at the beginning about your used version, about your used theme, ...
How can we help you if we do not know this?

Well, I can reproduce this in 5.6.23.
 

And I found the issue.
This error only occurs in the last row.
 



So, file a bug report.

A quick workaround is:
Create a second subquestion, but hide it by subquestion relevance
 

  

Joffm
 

Thank you Joffm. Sorry for didn't mentioned the version and al the rest. It was the first time writing in the community. Create a second subquestion and hide solved the problem. Thanks again

Please filema bug report.