Arianna Huffington

Profession: Novelist, film producer and screenwriter

Age: 53

Net worth: $54 million (£41.8 million) (2018)

The British novelist JK Rowling faced her fair share of obstacles and rejection when she was trying to publish her first book, Harry Potter and the Philosopher’s Stone. Once she managed to break through the publishing barriers, though, JK Rowling’s books became an instant hit seemingly overnight, turning the book series into films, merchandise and even adventure parks.