My friends accuse me of being too "anal" because I do the same thing with all the stuff in my house; I date everything also. They can't be bothered to stop one second to jot down the date and then wonder when that was purchased, etc. I write the date of purchase inside the refrigerator and freezer, on the outside of the washing machine, etc. I even write on a piece of masking tape the date when my water filter should be changed out and put it on my pitcher. We're all so smart, aren't we!!!!!