It once seemed that no celebrities were so Z-list that they did not merit their very own, beautifully (ghost)written autobiography. Even twentysomethings such as the Celebrity Big Brother winner Chantelle Houghton could command large advances.

But cash-strapped consumers are tiring of reading about celebrity lifestyles, and shops have slashed prices of such autobiographies for the crucial Christmas market.

HMV, which owns Waterstone's, said yesterday that shoppers' appetite for books was waning amid weakening consumer confidence, and pinpointed celebrity autobiographies as the weakest end of the market.

Sales of these life stories traditionally soar before Christmas. They account for about 20 or 25 per cent of sale for most of the year, but over the Christmas season that rises to between 50 and 55 per cent.

Simon Fox, the chief executive of HMV, said: “Sales of these books are down just over 5 per cent over the last five to six weeks.”

The returns on celebrity autobiographies are diminishing as the number of high-profile misfires grows. Every publisher wants another Peter Kay, whose self-penned autobiography The Sound of Laughter was the star of Christmas 2006, shifting a record-breaking 600,000 copies in its first two months on sale. Yet his is a hard act to follow.

Ms Houghton's Living the Dream, for which she received a reputed £400,000 advance from Random House, sold fewer than 5,000 copies in hardback. Michael Barrymore, the former game-show host who also featured on Celebrity Big Brother, earned £300,000 for Awight Now, but it sold poorly. Ashley Cole, the footballer and husband of the Girls Aloud and X-Factor star Cheryl Cole, was signed up for £250,000 for My Defence before the 2006 World Cup, but not only did England flop in the tournament, his book sold only 4,000 copies.

André Breedt, of Nielsen BookScan, a book data service, said: “Trade non-fiction - the category for celebrity autobiographies - is down about 3per cent year on year at the moment, although this contrasts with a particularly strong year last year. People just don't seem to be buying at the moment.”

Waterstone's recently began a half-price sale on celebrity books such as Parky by Michael Parkinson, Stephen Fry in America and Nigella Christmas by Nigella Lawson. Borders, Tesco and online retailers such as Amazon are offering similar deals.

Julie Walters, the actress most recently seen in Mamma Mia!, is topping the bestseller list for hardback non-fiction this year, with her autobiography That's Another Story, which has sold 215,955 copies in nine weeks. She received close to £1.5million for the book. By contrast, Being Jordan, the first volume of the glamour model Katie Price's life story, sold 335,649 copies in hardback.

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