What is the "Freedom Score" based upon? I find it strange that the USA has such a low score (in the 80's), though I do note that the censorship in the USA isn't

What is the "Freedom Score" based upon? I find it strange that the USA has such a low score (in the 80's), though I do note that the censorship in the USA isn't really as much state-driven, as it is corporate. I also noted that Iceland has a lower score than Norway, which seems odd to me, as it's for instance known to fervently support the integrity of servers stationed there. I've noticed that part of the reason Norway has less censorship than other countries, is because it's outside the EU (despite being a de-facto member). In several instances of using a VPN, things that were censored in the EU (I remember checking several EU countries) weren't cencored in either Norway or the USA.