I don’t know what the usual Goodreads-to-LibraryThing readership ratio is, but The Dog Stars‘ ratio is at least higher than all the other books on this list. If it actually is unusually high, it’d make sense that an unusually large fraction of the LibraryThing users who own it are Goodreads migrants.
I think that’s likely to be people importing their collections from Goodreads: something there’s apparently been a lot of lately.
I don’t know what the usual Goodreads-to-LibraryThing readership ratio is, but The Dog Stars‘ ratio is at least higher than all the other books on this list. If it actually is unusually high, it’d make sense that an unusually large fraction of the LibraryThing users who own it are Goodreads migrants.