I'm trying to pass the percentage that a user has scrolled on a page as a var ([see fiddle](http://jsfiddle.net/AndDZ/)). `$(document).scrollTop() / $(document.height() * 100` is great for starting at 0 -- the top of the page -- but when you get to the bottom, it only returns the position at the top of the scrollbar, not 100%. See fiddle to see what I mean.

Does anyone know a way to get 0 at the top and 100 at the bottom? Main thing is it has to be calculated on-the-fly: if someone's at 45.2667% of the page, I want that value passed as opposed to just at the top or at the bottom.