blank entries contained in the charts/graphs series listing

Go to charts graphs,
include all books
see that some series such as Chronicles of Narnia: Publication order contain a lot of "blank" entries that only have a number:

It looks like:
The Lion, the Witch and the Wardrobe by C. S. Lewis (1)
(1)
(1)
Prince Caspian by C. S. Lewis (2)
The Voyage of the Dawn Treader by C. S. Lewis (3)
The Silver Chair by C. S. Lewis (4)
The Horse and His Boy by C. S. Lewis (5)
The Magician's Nephew by C. S. Lewis (6)
The Last Battle by C. S. Lewis (7)
(5)
The Lion, the Witch and the Wardrobe | The Silver Chair | The Magician's Nephew | The Last Battle by C. S. Lewis (1, 4, 6-7)
(4)
(2)
The Magician's Nephew / The Lion, the Witch, and the Wardrobe / The Horse and His Boy by C. S. Lewis (1, 5-6)
(7)
The Magician's Nephew / The Lion, the Witch and the Wardrobe by C. S. Lewis (1, 6)
(1-3, 5)
Prince Caspian / The Voyage of the Dawn Treader by C. S. Lewis (2-3)
The Lion, the Witch and the Wardrobe / Prince Caspian / The Voyage of the Dawn Treader by C. S. Lewis (2-4)
The Silver Chair / The Last Battle by C. S. Lewis (4, 7)
The Chronicles of Narnia by C. S. Lewis
(1-7)

I would love to know how to get rid of those blank entries. I have a lot of series that suffer from this problem. I think what happened was that two works with a series entry were combined into one work, and both series entries were kept. I don't know that this is the current behavior on combination, but the above still occurs from when this might have been the combination behavior.

Sorry, this is charts/graphs, all books for which section? I didn't see any instances of this in https://www.librarything.com/stats/lorax/series

and on your equivalent

https://www.librarything.com/stats/al.vick/series the Narnia series looks OK as well. Transient issue or am I looking in the wrong place?

Verified. Looking into this.

You choose "All books" from the Your books|All books options.

Fixed.

Much improved! I like it a lot.