Across the nine main Star Wars films, there are a total of fourteen sunsets, representing an average of just slightly over 1.5 SsPF (Sunsets Per Film).
Taking into account the other canon films (Clone Wars, Solo, Rogue One), that number declines to 1.33 SsPF.
Star Wars 1: The Phantom Menace.
This film features a single sunset on Coruscant. There are also scenes at dusk on Naboo, but no suns are visible.
Sunset on Coruscant

Star Wars 2: Attack of the Clones.
The film features several scenes set at dusk on Theed and Geonosis, and two sunsets, one on Tatooine and one on Coruscant.
Sunsets on Tatooine

Sunset on Coruscant

Star Wars 3: Revenge of the Sith.
This film features three sunsets on Coruscant and Tatooine. There's also a dusk scene on Alderaan, but no sun is visible.
Sunset on Coruscant

Sunset on Coruscant (a few days later)

Sunsets on Tatooine

Star Wars 4: A New Hope.
This film features a single sunset scene on Tatooine. We also see a dusk scene on Tatooine, but no suns are visible.
Sunsets on Tatooine

Star Wars 5: The Empire Strikes Back.
This film features a single sunset on Bespin. Much of the action at the end of the film takes place at dusk on Bespin the following evening, but no suns are visible
Sunset on Bespin

Star Wars 6: The Return of the Jedi.
This film features a single brief sunset on Tatooine. There are also scenes at dusk on Bespin and Yavin 4, but no suns are visible.
Sunset on Tatooine

Star Wars 7: The Force Awakens
This film features a single sunset on Jakku.
Sunset on Jakku

Star Wars 8: The Last Jedi
This film features sunsets on Canto Bight and Ahch-To.
Sunset on Canto Bight

Sunset on Ahch-To

Sunsets on Ahch-To (the next day)

Star Wars 9: The Rise of Skywalker
This film features a single sunset on Bespin.
Sunset on Bespin

Rogue One: A Star Wars Story
This film features no sunsets at all.
Solo: A Star Wars Story
This film features a single sunset on Vandor-1
Sunset on Vandor-1

Star Wars: The Clone Wars
This film featured a single sunset on Tatooine. The entire film is set almost exclusively at dusk on a wide range of planets, but no sunsets are seen elsewhere.
Sunset on Tatooine
