Two decades of best-selling books trace new formats and changing reader tastes.


Who needs self-help books when you can read about Harry Potter, Katniss Everdeen or even Anastasia Steele?

As USA TODAY's Best-Selling Books list celebrates its 20th anniversary, an analysis shows reading tastes have shifted, boosting series for kids and teens, while erotica has gone mainstream.

Two decades ago, self-help was hot. That has given way to J.K. Rowling's boy wizard and Katniss, the tougher-than-tough heroine of Suzanne Collins' dystopian Hunger Games trilogy.

And coming on strong is Steele, who at 21 knows more about 19th-century literature than modern men until she meets a billionaire who likes kinky sex in E.L. James' erotic Fifty Shades of Gray trilogy.

Since USA TODAY began tracking best-sellers on Oct. 28, 1993, two transformative decades have roiled publishing. Online book sales, e-books and e-readers are on the rise.

Given all the changes in book selling and retailers contributing to the list, the two decades have been divided into three distinct eras with three No. 1 books:

- 1993 through 1998: John Gray's Men Are from Mars, Women Are From Venus, released in 1992, tops all titles during this period, when self-help dominated and most books were bought the old-fashioned way, at physical stores. Gray's publisher, Harper, reports selling more 9.5 million copies, including the 20th anniversary edition last year.


INTERACTIVE: 20 years of No. 1 titles on USA TODAY's Best-Selling Books list

- 1999 through 2008: Rowling's fantasy series triggered midnight book-release parties and got kids thinking reading is cool. Harry Potter and the Sorcerer's Stone, the first in the series, is No. 1 during this period, when Amazon popularized online book sales.

Rowling's U.S. publisher, Scholastic, reports 32 million copies in print of Sorcerer's Stone, released in the USA in 1998 and adapted as the first of the eight Potter films in 2001.

- 2009 to the present: Collins, building on the growing popularity of novels for teens, revived interest in dystopian literature in The Hunger Games, the first of a trilogy that's on its way, like Potter, to becoming a movie franchise.

The book is No. 1 for the current era, marked by the rise of e-books. Scholastic reports 28 million copies in print of the series' first book.

Scholastic's president, Dick Robinson, says that Rowling and Collins, as well as Stephenie Meyer (of Twilight , near the top of the lists for the past two eras), appeal to "a broad spectrum of readers — not just kids, but lots of grown-ups."

He notes that USA TODAY has one all-inclusive best-seller list, which, unlike other major lists, doesn't separate fiction, non-fiction, children's books or other formats and categories. Print and digital sales are combined on the single list.

"It's the most democratic list and shows just how popular children's and young adult books have become," Robinson says.