J.K. Rowling and the Harry Potter books

J.K. Rowling, a British author, is famous for her seventh-book Harry Potter series, which has sold over 500 million copies and inspired a blockbuster film franchise. Joanne Rowling was born on July 31", 1965, in Yate, England. She chose the pen name J.K., incorporating her grandmother's name, Kathleen.

After graduating from the University of Exeter, Rowling moved to Portugal in 1990 to teach English. She later married Jorge Arantes and had a daughter, Jessica, before their divorce. Rowling then moved to Edinburgh with her daughter. While struggling as a single mother, Rowling began writing the first Harry Potter book. The idea came to her on a train in 1990.

Despite getting several rejections, Rowling finally sold her first book, Harry Potter and the Philosopher's Stone for the equivalent of about $4,000; it hit shelves in June 1997. The second book in the Harry Potter series, Harry Potter and the Chamber of Secrets, came out in July 1998. The third book in Rowling's series, Harry Potter and the Prisoner of Azkaban, hit shelves in July 1999. In July 2000, the fourth volume in the series, Harry Potter and the Goblet of Fire was published and became the fastest- selling book in 24 hours ever. After a postponed release date, the fifth installment, Harry Potter and the Order of the Phoenix, hit bookstores in June 2003. The sixth installment, which was released in July 2005, sold 6.9 million copies in the United States in its first 24 hours. Harry Potter and the Half-Blood Prince was the biggest opening in publishing history.

The seventh book in the Harry Potter series, Harry Potter and the Deathly Hallows was released in July 2007, marking the conclusion of the series. Rowling has no plans for more Harry Potter books, but she hasn't entirely ruled out the possibility.

(Adapted from https://www.biography.com/authors-writers/jk-rowling)

How long was it from the publication of the first book to that of the last one?=>____________________________________