Remember to think of that cull check as a part of your income- and plan accordingly... I mean cull before they start losing too much condition that they are not worth anything...
That cow right now is probably worth $600-750 as hamburger- maybe more at the latest prices, but at the age she is could quickly deteriorate to be worth very little......
If you retain 10-20% of your heifers yearly and cull the same yearly-- unless you have some major problems with your herd that takes precedent in your culling, they should usually not get that old...And your herd should be improving from the new genetics your adding....