I didn’t believe it was possible to top 1980 or 1998, but then I looked at the top movies when I was 17 (yes, kids they had movies back then) and saw this list. I don’t know exactly which were the summer movies, but the fraction of films that opened in the summer have to qualify as one of the best years ever:

American Graffiti

The Exorcist

The Sting

Enter the Dragon

Paper Moon

Papillon

Serpico

The Way We Were

The Last Detail

The Day of the Jackal

Westworld

High Plains Drifter

Magnum Force

Walking Tall

Cinderella Liberty

Live and Let Die

The Paper Chase

Soylent Green

Amarcord

Sleeper