• According to the Association of American Publishers (AAP), US book publishing industry generated an estimated revenue of $25.82 billion, representing 2.71 billion units in 2018.
• The publisher revenue for adult fiction was $4.40 billion and $3.72 billion for children’s & young adult fiction in 2018, totaling $8.12 billion for the fiction category.
• Since trade books (fiction, non-fiction, and religious presses) had a revenue of $16.19 billion in 2018 and fiction and religious books generated $8.12 billion and $1.22 billion respectively, we can conclude that the publisher revenue for non-fiction amounted to $6.85 billion during the period (16.19-8.12-1.22).

Other Findings

• Non-fiction books showed the largest growth in revenue for publishers over the past five years with a 22.8% increase in adult non-fiction and a 38.5% increase in children’s & young adult non-fiction (2014-2018).
• According to Forbes, "2013 was the last year that the adult fiction category beat non-fiction in revenue (at $5.21 billion in revenue to non-fiction's $4.82 billion). Revenues for adult non-fiction have rapidly risen every year since: $4.97 billion in 2014, $5.59 billion in 2015, $5.87 billion in 2016, and finally $6.18 billion last year. In the same five-year period, adult fiction revenues dropped from a high of $5.21 billion in 2013 to 2017's low of $4.38 billion."