Considering those authors mentioned more than once in the Overall top 20 in each Year group, we find they aggregate as follows.
Jeff Kinney remains most popular author even with a decreased number of mentions, with 58 mentions in 2019, and 60 mentions in 2018. David Walliams is at number two, increasing his mentions from 31 to 35. Roderick Hunt also maintains his title at number 3 with 24 mentions, but of course his books are all for young children.
Roald Dahl remains at number four, although his mentions are down to 17 (from 20 last year). Julia Donaldson stays at number five, and her mentions now total 13 (one down from last year). Francesca Simon stays at number six with her mentions remaining the same. There’s a new entry at number 7 from R.J. Palacio.
Joint eighth on two mentions are John Boyne, Suzanne Collins, Judith Kerr, Jill Murphy, Michael Rosen, Dr. Seuss and John Steinbeck.