From Vox.com:
Conventionally, the most common way of gauging the most popular books in America has been looking at the New York Times' bestsellers list. But as we shift from reading on paper to screens, there's an interesting new option: Amazon's lists of the most-highlighted passages and most-highlighted books on Kindles around the world.
Amazon collects data on what its readers highlight most. The resulting most-highlighted lists are a fascinating record of reading as a whole.
Of the top 25 most-highlighted passages ever, a ridiculous 19 come from one of the books in the Hunger Games trilogy, including numbers 1, 3, 4, 5, and 6. Additionally, the three books rank as 3, 8, and 13 in the list of most-highlighted books of all time.
Part of this is simply due to the fact that Kindles have only become widely-used over the past few years, and The Hunger Games has been the most popular series during that time.
But the books' dominance in the rankings is still pretty amazing. The single most-highlighted passage, from Catching Fire ("Because sometimes things happen to people and they’re not equipped to deal with them.") was highlighted by 17784 Kindle users. No other passage from any book has gotten more than 9260 highlights.
Some of the 19 Hunger Games passages in the top 25 are important plot points, or are perhaps a little inspiring. But many are clearly there because they tap into adolescent ideas of romance.
The fifth-most highlighted passage of Kindle text of all time, for instance, highlighted by 8,500 readers, is
'I just want to spend every possible minute of the rest of my life with you,' Peeta replies."
Also interesting to note: When you take away The Hunger Games, the top 50 most-highlighted books include just eight other novels written since the start of the 20th century.