As of July 11, the top 20 bestselling Amazon titles, buoyed by mainstays like the 50 Shades books and the Hunger Games trilogy, have an average of 353 days on the bestseller list. There are a few newcomers--Artemis Fowl by Eoin Colfer and Batman: Earth One by Geoff Johns have each been on the chart for nine days--but they're outweighed by titles like Unbroken by Laura Hillenbrand (612 days in the top 100) and The Great Gatsby (539 days). StrengthsFinder 2.0 has had the longest residency in Amazon's top 100, clocking in at 1,793 days. By comparison, the top 20 Kindle bestsellers average 164 days in the top 100.

Amazon Top 20 Bestsellers (as of July 11)

1. Fifty Shades Trilogy Box Set by E.L. James (66 days)

2. Fifty Shades of Grey by E.L. James (117 days)

3. Fifty Shades Darker by E.L. James (117 days)

4. Fifty Shades Freed by E.L. James (117 days)

5. Gone Girl by Gillian Flynn (48 days)

6. Shadow of Night by Deborah Harkness (33 days)

7. A Song of Ice and Fire, Books 1-4 by George R.R. Martin (463 days)

8. The Hunger Games by Suzanne Collins (658 days)

9. Mockingjay by Suzanne Collins (893 days)

10. Unbroken by Laura Hillenbrand (612 days)

11. Bared to You by Sylvia Day (30 days)

12. How to Read Literature Like a Professor by Thomas C. Foster (299 days)

13. Catching Fire by Suzanne Collins (hardcover, 1,052 days)

14. StrengthsFinder 2.0 by Tom Rath (1,793 days)

15. Batman: Earth One by Geoff Johns and Gary Frank (9 days)

16. The Great Gatsby by F. Scott Fitzgerald (539 days)

17. Dream Team by Jack McCallum (9 days)

18. Wild by Cheryl Strayed (103 days)

19. Catching Fire by Suzanne Collins (paperback, 84 days)

20. Artemis Fowl by Eoin Colfer (9 days)