memory card retention?

Sorry to ask such a dim question which has in all probability already been asked a thousand times previously - but -
Has anyone out there in cyberspace got any idea how long data can be stored on a CF memory card - or any other card for that matter - before it leaks away? I am assuming the card is left on a shelf and is not powered in any way.

Regards

I've never seen any statistics with repect to this subject. Given that the memory card is really in its infancy in the grander scheme of things are we to assume that this will happen at some point in tme.

I know I had a CF card that was missing show up and when I checked the card the images on it were over 6 months old. No issues with them.

Not being a total techno-geek does this have to happen. I have old 5.25 and 3.5 disks for my computers and the data on them is still good (or at least the one I looked at not too long ago)

Their lifespan is 100 years with no data loss with normal use. Kingston says it will be there for 10 years untouched. You'll move it to another medium long before that... software and hardware lifespans are even shorter.