Interestingly, the authors make less on an eBook, while the publishers make more? That seems a bit odd! And do most authors really get $3.90 per book?
A quick search turned up some different rates, but seemed to be between 5 and 10% of the cover price, which suggests an author royalty on a $26 book is more likely to be around $2.60, and maybe even less (my own experience with trade paperbacks suggest it's less.)
This suggests that publishers are making more like $5.35. Not that I think publishers are having an easy time of it.