J. K. Rowling has made £5 a second in the past year as soaring sales of the final book in her Harry Potter series secured her place as the high-est-earning author in the world, according to Forbes magazine.

The 43-year-old writer, who composed much of her first book in a cafe because she could not keep warm in her council flat, earned six times more than James Patterson, the world’s bestselling crime author.

Her fortune, currently estimated to be £560 million, surpassed the Queen’s riches several years ago and is likely to extend her lead as royalties and earnings from film adaptations continue to pour in.

A world obsession with Harry Potter has resulted in 375 million book sales and the most lucrative film franchise ever. The first five films took £2.2 billion in box office receipts - more than all 22 James Bond films (£2.18 billion) or the six films in the Star Wars series (£2.08 billion). The sixth film is likely to rake in £500 million at cinemas and the seventh instalment could make double that figure because Warner Bros, its distributor, has decided to split it into two films.The mother of three had two children while creating the world of Hogwarts.

Forbes, the materialist’s Bible, noted that her £160 million annual income was more than the next nine writers put together. Lacey Rose, author of the report, said that Rowling’s place is likely to continue despite her announcement that she has no intention of writing another Potter book. “While the publishing industry has struggled to come up with a ‘happily ever after’ storyline in recent years, there’s still plenty of money to be made in the business of books,” she said. The adventures of the teen magician took the publishing world by storm in 1998, when Harry Potter and the Sorcerer’s Stone became a hit.

Rowling shares creative control over the movies and negotiated an undisclosed cut of the profits. She also receives a cut from toy merchandising machine, with Mattel earning an estimated £100 million plus million worth of Potter paraphernalia. Video games by Electronic Arts generate even more, and images of the boy wizard appear on everything from sticking plasters to sweets. An amusement park, the Wizarding World of Harry Potter, is being constructed in the Islands of Adventure area of Universal’s Orlando park.

Rowling, who has homes in Edinburgh, Perthshire and London, has said: “I know I am the luckiest woman in the world.” She is now devoting much of her energy and fortune to charity, including the Children’s High Level Group, which she founded. Last month she donated £1 million to the Labour Party.

Forbes’ top-earning five authors are: J.K. Rowling £160 million; James Patterson £26.7 million; Stephen King £24 million; Tom Clancy £18.7 million; Danielle Steel £16 million.

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