Morrison isn’t in the top 100 on Amazon anymore (she was for about eight weeks in the US, earlier this year), but she too has seen the benefits of the adult coloring craze. In all of last year, she sold 15,414 books on Amazon. This year, in half the time, she has sold 43,420.

The sharp increase took her by surprise, she says. “Have they wanted to do this all along, they just were afraid to tell their friends?” She thinks people certainly do it for fun, but she also gets letters that demonstrate the positive effects of coloring books—a prison recently requested a batch for inmates who use them for therapy and stress release, and recovering surgery patients have told her that coloring her books is the only way they manage to stay put.

You don’t actually have to pay money to color, by the way. One of the Facebook groups devoted to adult colorers, called Coloring Pages for Adults, regularly posts designs that you can print out and play with at your leisure.

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The featured image in this post is courtesy of Flickr user Eugene Kim.

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