Even I have faced similar issue recently - might be a bug.
Interesting thing here is, when I tried to sort the data in matrix based on Total Column (With Both Rows and Columns turned ON), I observed that the data did get sorted correctly based on Totals. So, the issue seems to be just with the display of numbers
in Totals columns.
I am trying to figure out if there is any alternative to resolve this issue. Will post it here if I come across any.
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