Sorry, but the total revenues are higher for the typical R-rated movie. That's why they keep making them.
All-Time Worldwide Boxoffice
Many many Gs, PGs, and several PG-13s. Very few Rs.
1. Titanic (1997) $1,835,300,000
2. The Lord of the Rings: The Return of the King (2003) $1,129,219,252
3. Harry Potter and the Sorcerer's Stone (2001) $968,600,000
4. Star Wars: Episode I - The Phantom Menace (1999) $922,379,000
5. The Lord of the Rings: The Two Towers (2002) $921,600,000
6. Jurassic Park (1993) $919,700,000
7. Shrek 2 (2004) $880,871,036
8. Harry Potter and the Chamber of Secrets (2002) $866,300,000
9. Finding Nemo (2003) $865,000,000
10. The Lord of the Rings: The Fellowship of the Ring (2001) $860,700,000
11. Independence Day (1996) $811,200,000
12. Spider-Man (2002) $806,700,000
13. Star Wars (1977) $797,900,000
14. Harry Potter and the Prisoner of Azkaban (2004) $789,458,727
15. Spider-Man 2 (2004) $783,577,893
16. The Lion King (1994) $783,400,000
17. E.T. the Extra-Terrestrial (1982) $756,700,000
18. The Matrix Reloaded (2003) $735,600,000
19. Forrest Gump (1994) $679,400,000
20. The Sixth Sense (1999) $661,500,000