The hoped for post-election and holiday season sales bounce does not seem to be materializing. Unit sales of print books were down almost 6% between Thanksgiving week and the week ended December 18, 2016 compared to the similar period in 2015 at outlets that report to Nielsen BookScan.

Perhaps the most worrisome for booksellers and publishers is that the worst sales week was the most recent, with units off 11% in the week ended December 18, compared to the week ended December 20, 2015. Sales in the most recent week were weakest in the mass merchandiser channel, falling 24%. Sales through the retail and club channel were down 8%.

The lack of a big book or hot category (like last year’s adult coloring books segment) appears to be hurting sales. Unit sales were down in all four major segments last week. The juvenile nonfiction category had an 18% decline in unit sales compared to a year ago, while sales of adult fiction were off 12% in the week. Unit sales of juvenile fiction were down 9% and adult nonfiction unit sales were off 8%, according to BookScan.

The bestselling print book last week was Diary of a Wimpy Kid: Double Down by Jeff Kinney, which sold just under 126,000 copies. Killing the Rising Son by Bill O’Reilly and Martin Dugard was the top seller in adult nonfiction last week (and #2 in the country), selling 104,000 copies.

John Grisham’s The Whistler sold 71,000 copies to top the adult fiction category last week and had a 31,000-copy lead over second place A Man Called Ove by Fredrick Backman. First 100 Words by Roger Priddy was the top seller in the juvenile nonfiction segment last week, selling about 31,000 copies.

Last year at this time, five books sold more than First 100 Word's 31,000 copy figure, including First 100 Words itself, which sold over 70,000 copies a year ago. The top-seller in the segment in the week ended December 20, 2015 was Laugh Out Loud Jokes for Kids by Rob Elliot, which sold nearly 108,000 copies, while two Johanna Basford adult coloring books combined to sell almost 150,000 copies.

In adult nonfiction, adult coloring books took nine places among the top 20 bestsellers in the category for the week ended December 20, selling a combined total of about 350,000 copies in the week.

Even with the so-far-disappointing holiday season, total unit sales through December 18, 2016 were still up about 2% over the same period a year ago.