How the Box Office has evolved in the Star Wars franchise since 1977

With the exception of Ep.II, Star Wars movies have been always been the top one in the yearly box office since 1977. This is how big were their box office in comparison with the second highest box office of the same year (except for episode 2, which is compared with the first one).

Star Wars 2.72x
The Empire Strikes Back 2.02x
Return of the Jedi 2.33x

The Phantom Menace 1.47x
Attack of the Clones 0.74x
Revenge of the Sith 1.30x

The Force Awakens 1.43x
Rogue One 1.09x
The Last Jedi 1.07x

It doesn't look good for episode 9...