My first idea was to fill a bug for that [1]. But looking for the bug on the reports code, I found that the problem was in C4::Circulation. So filled a bug for it [2] and provided regression tests and the fix. Cool.

But what about the wrong data on the statistics table? Basically, all returns have the wrong itemtype (NULL). Should we fix that table's data? Should we make the report do the proper JOIN operation on the items table? I'd go with the first option, but probably worth discussing, because there are other bugs related to how the 'statistics' table have been filled. [3]

Regards

[1| http://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=14531

[2] http://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=14598

[3] http://bugs.koha-community.org/bugzilla3/show_bug.cgi?id=11229

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