Earlier quoted context omitted.
Keep in mind that FB can, and does, track your browser usage whether you are logged in or not. So even though some info may not currently be in the graph, they certainly have a pretty good dossier covering everything you do on the internet. It's not only what you put on your FB that counts, it's anything you have done on the internet from a browser.
Interesting that you believe FB can magically track 100% of your browsing history even if you are not logged into facebook and not on a site with FB integration. However, this is something google does for sure. Thanks to chrome and search integrations in other browsers.
[1] - https://www.eff.org/deeplinks/2010/01/tracking-by-user-agent