Looking at Box Office Mojo, the Top 10 All-Time Domestic box office champions are:
1. Avatar
2. Titanic
3. The Avengers
4. The Dark Knight
5. Star Wars: Episode I - The Phantom Menace
6. Star Wars: Episode IV - A New Hope
7. The Dark Knight Rises
8. Shrek 2
9. E.T.: The Extra-Terrestrial
10. Pirates of the Caribbean: Dead Man's Chest
1-7 are pretty revealing. It consists of:
- Batman
- Star Wars
- The Avengers
- James Cameron
2015 consists of:
- Batman/Superman
- Star Wars: Episode VII
- The Avengers 2
^ Three movies all fighting their way for a spot in the Top 10 of All-Time.
I don't think a year like 2015 has ever happened before.
It could either be unprecedented with audience turn-outs, or it could be three juggernauts canceling each other out because they have to share too many tickets, resulting in a disappointing year.
If Avatar 2 were coming out in 2015, it would be almost catastrophic.
I have a feeling that 8-10 are being bumped off without a doubt (Shrek 2, E.T., Pirates).