Hollywood's summer of monster movies makes audience yawn

Hollywood unleashed a noisy barrage of monsters, mutants and superheroes this summer, blowing up the world several times, but the roster of blockbusters did not quite provoke the reaction expected: America yawned.

Studios spent hundreds of millions making and promoting individual movies for the expected seasonal rush to multiplexes, only for their films to run out of steam within days and be rechristened "summer bummers".

Domestic summer box office revenue fell approximately 15%, one of the biggest year-on-year declines in decades and the final tally may come in below $4bn (£2.4bn) for the first time in eight years.

Big budget offerings including Godzilla, The Amazing Spider-Man 2, X-Men: Days of Future Past and Transformers: Age of Extinction did not exactly bomb. Opening weekends brought in ticket sales of $90m-$100m. But then, like King Kong tumbling from the Empire state building, they crashed to earth.

In their second weekend Spider-Man fell 59%, Godzilla 67%, and X-Men and Transformers 64%. Now, with Labor day approaching, headlines like "Summer bummer" and "Summer of slump" are capturing Tinseltown's bleak mood.

"What other product spends millions in preparing for launch – and in six weeks it's gone?" asked Arthur de Vany, author of Hollywood Economics: How Extreme Uncertainty Shapes the Film Industry. "You put all this money up front and all you really have is a can of celluloid. You don't really know what's going to happen."

Unexpectedly impressive performances by Guardians of the Galaxy and Teenage Mutant Ninja Turtles in August, traditionally summer's slowest month, have only partially lightened the gloom. Exceptional circumstances, such as the World Cup and the absence of a Pixar film, did not help.

Not for the first time, studio executives are struggling to fathom the industry's mysterious economics. Last summer there were spectacular flops such as The Lone Ranger and RIPD, failures that entered Hollywood lore, but at the same time there were record box office receipts of $4.75bn thanks to hits such as Despicable Me 2 and Iron Man 3. The purple patch lasted into the first half of this year, raising hopes of a bumper summer, and there have been critical and commercial successes: Disney's Maleficent, a reworking of Sleeping Beauty starring Angelina Jolie; 20th Century Fox's Dawn of the Planet of the Apes, a sequel to the 2011 reboot; Marvel's Guardians of the Galaxy, which launches a new franchise; and the Turtles, which tapped nostalgia for the original TV series and movies.

But the steep drop-offs after opening weekend are a big concern. The producer Robert Evans famously compared a movie's opening to a parachute jump: "If it doesn't open, you are dead."

Still true, but opening strongly is not enough if hardly anyone subsequently turns up. Godzilla, which roared to $93m domestic box office opening, three months later hovers at $200m, according to Box Office Mojo. Transformers, the only film to exceed a $100m domestic opening this summer, has topped out at around $243m, the lowest in the four-film franchise.

The original Star Wars fell just 15% week on week and lasted in theatres for months. Now you would be lucky (or unlucky, depending on taste) to find the giant lizard or alien robots on a big screen in the US.

One possible explanation is that the films are just not good enough, but Hollywood has focused on other theories.

Paul Dergarabedian, an analyst for the entertainment data firm Rentrak, blamed studios for packing offerings between late May and July, with one hyped blockbuster immediately following another. "Summer becomes a box office traffic jam. It gets congested. Movies get a very small window in which to work. The bigger they are the harder they fall."

Marketing a single blockbuster in the US costs between $75m and $100m, a huge outlay that makes profitability more elusive – but does not benefit the industry as a whole.

"Advertising simply shifts market share back and forth, it doesn't expand the total market," said de Vany. "The movie that doesn't have the goods, if it's been highly anticipated, can be ruthlessly murdered by an audience with the speed of light."

There are lessons from the "summer bummer" – one is that strong female leads, still a rarity, can deliver better longevity. Maleficent fell 50% in its second week. Lucy, a medium-budget offering starring Scarlett Johansson, fell 58%.

Another is that the rest of the world, accounting for 70% of revenue, matters more than ever, especially China, which is expected to overtake the US box office by 2018. Paramount's Transformers earned $300m in China, with the depiction of ass-kicking Chinese authorities resisting the aliens, versus bumbling American officials, doing its distribution no harm at all.

The other lesson is to not scrunch so many blockbusters into a short period. Warner Bros, which originally slated Batman v Superman for May 2016, recently announced the film will instead open in March of that year to avoid a showdown with another superhero.