As an entirety of the web, since I'd like to say a majority of the web are personal websites, blogs, business info, social media sites, I'd say 50 to 65%.
But as for finding information on history and other topics that would require research I'd go with a little bit less, 30 to 40%.
To be kind of a devil's advocate, what is considered correct? Some people may believe that their version is correct although to others it could seem kind of crazy and totally far fetched.
For example, those who that believe Elvis was still alive, that's crazy but I mean realistically there is no true way to prove it, it could've been an elvis look-a-like who passed away and Elvis snuck off and went off the grid and lived in a quiet peaceful place, not to be bothered by people again.