on the same day in 1948. , Guinness World Records listed Christie as the best-selling fiction writer of all time. , her novels had sold more than two billion copies in 44 languages. Half the sales are of English-language editions, and half are translations. According to Index Translationum, , she was the most-translated individual author. Christie is one of the most-borrowed authors in UK libraries. She is also UK's best-selling spoken-book author. In 2002, 117,696 Christie audiobooks were sold, in comparison to 97,755 for J. K. Rowling, 78,770 for Roald Dahl and 75,841 for J. R. R. Tolkien. In 2015, the Christie estate claimed And Then There Were None was "the best-selling crime novel of all time", with approximately 100 million sales, also making it one of the highest-selling books of all time. More than two million copies of her books were sold in English in 2020. Legacy In 2016, the Royal Mail marked the centenary of Christie's first detective story by issuing six first class postage stamps of her works: The Mysterious Affair at Styles, The Murder of Roger Ackroyd, Murder on the Orient Express, And Then There Were None, The Body in the Library, and A Murder is Announced. The Guardian reported that, "Each design incorporates microtext, UV ink and thermochromic ink. These concealed clues can be revealed using either a magnifying glass, UV light or body heat and provide pointers to the mysteries' solutions." Her characters and her face appeared on the stamps of many countries like Dominica and the Somali Republic. In 2020, Christie was commemorated on a £2 coin by the Royal Mint for the first time to mark the centenary of her first novel, The Mysterious Affair at Styles. Adaptations Christie's works have been adapted for cinema and television. The first was the 1928 British film The Passing of Mr. Quin. Poirot's first film appearance was in 1931 in Alibi, which starred Austin Trevor as Christie's sleuth. Margaret Rutherford played Marple in a series of films released in the 1960s. Christie liked her acting, but considered the first film "pretty poor" and thought no better of the rest. She felt differently about the 1974 film Murder on the Orient Express, directed by Sidney Lumet, which featured major stars and high production values; her attendance at the London premiere was one of her last public outings. In 2016, a new film version was released, directed