Lagardère, parent company the Hachette Book Group, reported that total sales in its publishing group fell 1.6% in 2018 compared to 2017, dropping to €2.52 billion. Earnings for the company will be released in March.

In the U.S., HBG CEO Michael Pietsch credited a strong fourth quarter as contributing to “another solid year of revenue growth.” In the fourth quarter, sales at HBG rose 6.3% over the comparable period a year go. Among the drivers in the fourth quarter were bestselling novels from such authors as Nicholas Sparks, Michael Connelly, James Patterson, Robert Galbraith (a.k.a. J.K. Rowling), and Neil Patrick Harris. Pietsch also cited strong backlist sales from Jen Sincero (You are a Badass), and Hugo Award-winner N.K. Jemisin’s Broken Earth trilogy.

Pietsch also cited “significant growth in downloadable audio” and sales growth via HBG distribution clients such as Abrams (Jeff Kinney’s Diary of A Wimpy Kid: the Meltdown) and Chronicle (Sherri Duskey Rinker’s Construction Site on Christmas Night).

E-books accounted for 7.9% of 2018 Lagardère publishing revenue, up from 7.1% in 2017. Digital audiobooks represented 2.7% of revenue, up from the 2.0% reported in 2017.