How much percentage of Tomb Raider is story?

How much percentage of Tomb Raider is story? Thats pretty much 50% of the main story, and almost half of the games collectibles are there. It goes by pretty quick once you get all of them, as its the largest area by far, and the other areas dont have anywhere close to the same #.

Thats pretty much 50% of the main story, and almost half of the games collectibles are there. It goes by pretty quick once you get all of them, as its the largest area by far, and the other areas dont have anywhere close to the same #.