Mr. Haruki Murakami's latest novel, "Colorless Tsukuru Tazaki and His Years of Pilgrimage," his first since the publication of "1Q84" about three years ago, sold a million copies in seven days after it hit the stands.

The publisher, Bungei Shunju, printed 500,000 copies in advance of the April 12 publication date in anticipation of huge demand — an unprecedented move for a novel. On April 12, it decided to print 100,000 more copies — another unprecedented move. On April 30, during Golden Week, it decided to print another 50,000.

The publisher had not disclosed the content and the design of the new book cover in advance during its pre-publication PR campaign, but it did release the title and a comment by the author to get people's attention. While such efforts helped to boost sales, there were already many people looking forward to reading Mr. Murakami's new book — many more than the publisher had expected — and this was the fundamental reason for its record-breaking sales.