Jk Rowling has been steadily earning a fortune through her Harry Potter series. Well, let's not mince words - JK Rowling has made more money in the last 20 years than most people will make in their lifetime. Or in two lifetimes. Or five. What's more, is that this phenomenal achievement shows no signs of stopping, as the author has just added a further 36 million USD (20 million GBP) to her fortune - only 24 hours after the sixth book of the boy wizard series went on sale.

JK Rowling has recently released the sixth book in her 'Harry Potter' series
JK Rowling has recently released the sixth book in her 'Harry Potter' series

'Harry Potter and the Half-Blood Prince' hit the shelves at one minute past midnight on Saturday 16th July, 2005, greeted by long queues of ecstatic fans, going on to sell over two million copies by closing time on 17th July. Rowling's previous entrée into the series, 'Harry Potter and the Order of the Phoenix', saw its release in 2003, causing the rags-to-riches British author the chance to sell 1.7 million copies in the UK and 7 million in the US.

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As the series becomes more and more popular and successful, more people are exposed to it and have a chance to read. This sixth instalment is predicted to dramatically exceed previous sales records, as experts in the publishing world predict that the worldwide sales for the book will be over 10 million. One publishing insider correctly predicted: "All estimates are that this book will be even bigger than the last one. I think we should expect 2 million sales in Britain on the day of publication." 

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This makes that '10 million worldwide' goal appear even more achievable, and sales of that scale are likely to make a tidy little sum for Rowling. When you also consider the payday she is likely to receive later in the year when the adaptation of her fourth book, 'Harry Potter and the Goblet of Fire', hits cinemas, its not difficult to see why she is one of the highest earning women in the entertainment industry. 

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