Hi Stu,
The formats of negative numbers are set from Excel client side.
I make a simple sample and the formats displayed normally in my local. Here is the result.
Could you please do some tests and make sure if your issue is reproducible?
If so, could you please upload the document to following workspace so that I can do further investigation.
Workspace URL: (https://sftemea.one.microsoft.com/ChooseTransfer.aspx?key=e2f7de56-178b-4b21-ac46-7fa5a4a0d769)
Workspace Password: nCfF%3wuxr
Lambert Qin
TechNet Subscriber Support in forum
If you have any feedback on our support, please contact mtngfb@microsoft.com
Sincerely,
Lambert Qin
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