The predictions are notoriously bad, and in fact, do not help that much.
Take a look at
http://www.rwjf.org/files/publications/books/1997/chapter_08.html
Which was referenced by this one
http://www.lifetree.org/timeline.html
thanks, hocndoc. (I think!)
It's about 1 pm, I'm bleary-eyed and about saturated with downer-stuff for tonite.
To bed, to bed - the better to fight the morrow