His latest book is Follow The Money, but economist David McWilliams is counting it. The author has earned €450,000 from a two-book deal from Gill & Macmillan, even though the first title was a commercial flop and he has apologised for writing key sections of the second one.

Signed in 2006, McWilliams’ contract with Gill & Macmillan represented the biggest advance paid by an Irish publisher to a non-fiction author. It followed the success of The Pope’s Children the previous year, which sold almost 70,000 copies, grossing over €1.6m. His second book, The Generation Game, was a disappointment, selling fewer than 14,000 copies in Ireland and 400 overseas. This puts pressure on Gill & Macmillan to make a success of Follow The Money, published last week. It needs to sell an unlikely figure of 90,000 copies to justify the investment in McWilliams.

Follow The Money got extensive media coverage last week, due to McWilliams’s revelations about private meetings with Brian Lenihan, the finance minister, during the banking crisis in autumn 2008. The author has apologised for betraying Lenihan’s trust.

“I messed up. If I could write if again, I would not tell the details of that meeting because it was unfair,” he told Gerry Ryan on 2fm.

He also apologised to Miriam O’Callaghan, the RTE presenter, for likening her on-air interviewing technique to a seduction and for characterising her as flirting with guests. McWilliams admitted that he had misjudged his comments. Gill & Macmillan said there were “no issues” with the author over the way the book was edited. The first week’s sales figures will not be known until next Tuesday.

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