Shifting tastes in literature may be the reason for a drop in the price of books.
Statistics New Zealand figures show the price of books fell by 14% in the March quarter.
Statistics New Zealand says a change in the types of books that make up the best-seller lists is partly responsible.
The index is based on the top 10 adult novels, top 10 e-books and the top 10 children's titles, and the popularity of cheaper books makes a difference to the price of books overall.
The chief executive of Booksellers New Zealand, Lincoln Gould, says some publishers have also reduced their prices.