The code is only supposed to be on the last page of your document.
It is supposed to disappear (not show up) when you have display of field codes turned off.

It simply creates a new, blank, page at the end of the document if there are otherwise an odd number of pages.

I suppose, to keep track of it, you could put an end mark, like -30- at the end of your document before the code.

If you want to check and see that it is still there, press Alt+F9 to display field codes. Then press the combination again to hide them.

Note, I marked this as solved, because the field provided does what you requested. Remember, the field has to be updated before printing to work. If you are looking for something different, let us know.