1. Harry Potter and the Sorcerer's Stone (2001): $974.8 million
2. Harry Potter and the Chamber of Secrets (2002): $879.7 million
3. Harry Potter and the Prisoner of Azkaban (2004): $796.7 million
4. Harry Potter and the Goblet of Fire (2005): $896.3 million
5. Harry Potter and the Order of the Phoenix (2007): $938.2 million
6. Harry Potter and the Half-Blood Prince (2009): $934.2 million
7. Harry Potter and the Deathly Hallows - Part 1 (2010): $960.3 million
8. Harry Potter and the Deathly Hallows - Part 2 (2011): $1.342 billion
In terms of audience size, it's difficult to provide an exact number of people who have watched the Harry Potter films, as the availability and accessibility of the movies vary across countries and regions. However, it's safe to say that the Harry Potter series has a massive global fan base, with fans from all over the world enjoying the magical world created by J.K. Rowling.