They're no page-turners, but that's how you know they're good.
Adult coloring books became a cult sensation in 2015, revered for their therapeutic and nostalgia-inducing effects.
Now a new batch of data from Publishers Weekly reveals adult coloring books had something of a magic touch last year. Whenever an adult coloring book took on a particular theme, that entire category saw big jumps in sales.
"It's difficult to overstate the impact adult coloring books had on print sales last year," Jim Milliot wrote in PW's report.
For example, four of the top 10 best-selling books on Amazon are coloring books.
Perhaps unsurprising, the biggest boosts came in the Art/Architecture/Design/Photography category of adult non-fiction, where sales increased by 60% over 2014.
Other categories included Crafts/Hobbies/Antiques/Games and the Self Help category, which saw 35% and 15% increases, respectively.
Meanwhile, categories that never crossed paths with adult coloring books tended to see no change in popularity, or sometimes even a dip. The Cooking/Entertaining category held steady, for example, while Computers and Humor saw decreases of 9% and 5%.
Adult coloring books even managed to transcend their intended audience by helping to increase sales of juvenile non-fiction. As PW reports, titles such as "Secret Garden" and "Enchanted Forest" — each subtitled "An Inky Quest & Coloring Book" — were also classified as children's books.
The benefits of coloring — adult or otherwise — seem to mostly involve stress relief. Diehard fans of the activity report feeling a sense of calm wash over them simply by filling in tiny slivers of a bird's wing or an ornate paisley.
Unlike drawing or painting, coloring comes with a predetermined set of constraints — but not too many. Colorists, as they're called, still have every opportunity to veer outside the lines while still knowing the final product won't be a disaster.
Coloring's fun. And mindless. It also requires just the right amount of focus without being an energy suck. You can dip your toe in it for 15 minutes or let yourself wade for hours.
And after you finish your other way less fun adult tasks, you can pick up right where you left off.
