The category was boosted by a number of coloring books, led by Animal Kingdom: Color Me, Draw Me (Lark), which sold 332,000 copies.

Jim Milliot and Jonathan Segura reporting for publishersweekly.com, have a roundup of book sales in 2015 at outlets that report to Nielsen BookScan.

Here are the highlights and you can read the rest of the story here.

It's difficult to overstate the impact adult coloring books had on print sales last year, with the coloring-book craze driving large gains in several categories. The hottest category in 2015 was art/architecture/photography, which had a 60% increase. The biggest drop was Occult/Psychological/Horror at minus 33%.

Unit Sales by Category, 2014-2015 (in thousands)

	2014	2015	% Change
Adult Non-Fiction
Art/Architecture/Design/Photography	6,984	11,172	60%
Biography/Autobiography/Memoir	22,803	23,544	3%
Business/Economics	16,604	17,155	3%
Cooking/Entertaining	15,492	15,495	0%
Computers	4,652	4,234	-9%
Crafts/Hobbies/Antiques/Games	8,485	11,486	35%
Health/Fitness/Medicine/Sports	21,574	21,557	0%
History/Law/Political Science	15,220	17,132	13%
House & Home/Gardening	2,130	3,184	49%
Humor	4,897	4,660	-5%
Performing Arts	7,706	8,321	8%
Reference	31,989	33,266	4%
Religion/Bibles	35,798	35,930	0%
Self Help	9,848	11,279	15%
Travel	7,417	7,620	3%
General Non-Fiction	28,533	30,009	5%
Total Adult Non-Fiction	240,130	256,042	7%
Adult Fiction
Classics	7,578	9,985	32%
Occult/Psychological/Horror	3,329	2,218	-33%
Religion	4,174	4,414	6%
Fantasy	7,526	6,600	-12%
Science Fiction	4,142	5,964	44%
Suspense/Thrillers	20,111	21,783	8%
Action Adventure	2,239	2,285	2%
Graphic Novels	8,669	10,591	22%
Western	2,232	2,186	-2%
Mystery/Detective	14,304	12,533	-12%
Romance	30,885	28,031	-9%
General Fiction	33,524	35,101	5%
Total Adult Fiction	138,712	141,690	2%
Juvenile Non-Fiction
Animals	4,625	5,128	11%
Biographies/Autobiographies	3,979	4,253	7%
Concepts	3,790	4,296	13%
Education/Reference/Language	6,496	7,651	18%
Games/Activities/Hobbies	12,362	13,703	11%
History/Sports/People/Places	11,232	12,753	14%
Holidays/Festivals/Religion	3,895	4,073	5%
Social Situations/Family/Health	2,502	2,766	11%
Total Juvenile Non-Fiction	48,882	54,624	12%
Juvenile Fiction
Animals	9,051	10,112	12%
Classics	9,981	10,161	2%
Concepts	8,909	9,307	4%
Science Fiction/Fantasy/Magic	45,511	44,578	-2%
History/Sports/People/Places	14,107	13,550	-4%
Holidays/Festivals/Religion	8,621	9,418	9%
Social Situations/Family/Health	27,815	24,932	-10%
General	52,690	49,325	-6%
Total Juvenile Fiction	176,685	171,383	-3%