Calc: Create a copy of a sheet without a reference to the old sheet

So I have a document with that equation “=($Dezember.E9-$Dezember.D9)*24”. I’m right clicking on the sheet with the name “Dezember” and click on “Move or Copy Sheet…”.
When I’m choosing to move the equation changes to the new name. But when I’m choosing to copy the equation doesn’t change. How can I prevent this?

I just want a copy of an old sheet and work with that copy. Because this messy references that’s not possible for me.

Btw. your tag system seems to be broken.

(Suspicion: Your spreadsheet document was once created with Excel - 2003 e.g. If you still save it in the alien format there is no way to get rid of your problem. It’s due to Excel oddities then.)

Any sheet references are adapted if a sheet is renamed. This applies if you rename the sheet directly and as well if you use the ‘Move…Copy’ tool for the purpose.

Using the ‘Copy’ option to create a new sheet will leave absolute sheet references unchanged but adapt relative ones. Please make sure to understand that the result will depend on the position you create the new sheet in if the sheet reference does not point to the respective sheet itself. Moving an already existing sheet to a different position will not change any references. This is analoguous to the behaviour of cell references.

(Please also note: Sheets created with older versions of MS Excel do not know relative sheet references. Saved in .xls format all the sheet references are known to be functionally absolute even if displayed by old Excel without the $-sign. To be compatible LibO opening a spreadsheet documnet from such a file will make the sheet reference excplicitly absolute then to avoid ambiguities. Stick to the native .ods format using Calc.)

By the way: Many posts in different fora show that splitting data in monthly sheets (or in a similar way) can cause very annoying problems.