Bill wrote:
The clock on my range has never kept correct time, yet it keeps running and
using electricity. (Small amount, but many little things like this can add
up.)

So I pulled my electric range out from the wall, unplugged it, and
disconnected the clock. (Only do this if you know what you are doing.)
....

If you can even measure the difference...

And, of course, by disconnecting the range clock you've also disabled
the auto-on/off feature...

As an aside, it would seem quite unusual for a wall-sourced electric
clock to not be pretty accurate since grid frequency is normally pretty
precise.
--