After posting an 18.5% increase in the first six months of 2021, unit sales of print books declined 2% in the third quarter, compared to the same period last year, at outlets that report to NPD BookScan. Despite the quarterly drop, unit sales were still up 11% in the nine months ended October 2.

The third period dip was expected, as last year’s third quarter saw a number of big adult nonfiction bestsellers, including a mix of Trump-related titles—Mary Trump’s Too Much and Never Enough and In the Room Where it Happened by John Bolton—and books on social justice, led by White Fragility by Robin DiAngelo and How to Be an Antiracist by Ibram X. Kendi. For the quarter, adult nonfiction unit sales fell 7.9% but were still ahead 7% in the year to date. The top adult nonfiction title through the first nine months of 2021 was Mark Levin’s American Marxism, which sold nearly 860,000 copies.

The sales decline in juvenile nonfiction was also no surprise, as the category enjoyed a huge sales spike for much of 2020, driven by a host of books that helped parents teach and entertain their children at home. Interest in those books has softened as schools have slowly reopened, and print unit sales in juvenile nonfiction were down 15.9% in the quarter and 7.7% in the year to date. Through the first nine months of 2020, Big Preschool Workbook had sold nearly 649,000 print copies and My First Learn-to-Write Workbook by Crystal Radke sold almost 595,000 copies; this year so far, those titles have sold about 306,000 copies and 300,000 copies, respectively.

While nonfiction sales have declined as the year has moved on, fiction remains solid, even as its growth rate cooled in the third quarter. Adult fiction sales rose 26.6% through October 2, compared to the nine months ended Oct. 3, 2020. The Boy, the Mole, the Fox and the Horse by Charlie Mackesy, published in October 2019, was the top title in the category so far this year, selling almost 697,000 copies. Kristin Hannah’s newest novel, The Four Winds, was the #1 new release, selling about 628,000 print copies.

The YA fiction category managed to post a 32.7% increase in unit sales in the first nine months of the year, even as it had to deal with comparisons to two blockbusters in 2020; The Ballad of Songbirds and Snakes by Suzanne Collins sold close to 1.1 million copies through the first nine months of 2020, and Midnight Sun by Stephenie Meyer sold almost 985,000 copies in that same period.

Helping to offset those big numbers this year were several BookTok-driven books, including They Both Die at the End by Adam Silvera, which sold approximately 517,000 copies, as well as books tied to streaming series or films, including Shadow and Bone by Leigh Bardugo, which sold about 222,000 copies. (Also, Midnight Sun has sold another 268,000 copies in 2021.)

Juvenile fiction sales rose 11.5% in the year to date, helped by the continuing popularity of Dav Pilkey’s Dog Man series. Mothering Heights (Dog Man #10) was the top title overall so far this year, selling just over one million copies. Last year at this point, Pilkey’s Grime and Punishment (Dog Man #9) was #1 in the category, selling about 590,000 copies.