Bryan Alexander

USA TODAY

The autumn box office is falling, down about 16% from the same period last year, according to the tracking service comScore.

Post-summer moviegoers have shelled out $807 million at the box office since Sept. 6, including $24.7 million this weekend for Ben Affleck in The Accountant.

In a record-breaking 2015, the box office brought in a robust $960.8 million for the same period (Sept. 8 through Oct. 18).

No film this fall has truly broken out like Matt Damon's The Martian ($228.4 million total), says Jeff Bock, senior box-office analyst for Exhibitor Relations. Not Affleck (Damon's longtime friend) in The Accountant, nor Tom Hanks in Sully — though the latter has been the biggest fall performer ($118.4 million to date).

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"Sully has been a decent hit, but not anything like The Martian," says Bock. "We just haven’t had that overwhelming box-office hit this year that really drives the marketplace."

2016's animated Storks (now at $59.1 million) and Miss Peregrine's Home for Peculiar Children ($65.8 million) "could have filled that breakout spot but didn't quite fully connect with audiences," says Bock.

The increasingly crowded entertainment marketplace plays a large factor, says Paul Dergarabedian, senior media analyst for comScore.

That's demonstrated by sports fan Ben Affleck holding up the red carpet at the premiere for The Accountant so he could watch his Boston Red Sox play the Cleveland Indians in a key playoff game. Further, the historic news-making election battle between Donald Trump and Hillary Clinton is increasingly taking eyeballs, says Dergarabedian.

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"The election is adding a layer of noise to the entertainment landscape," says Dergarabedian. "It's impossible to quantify, but a lot of people are caught up in this election. And it’s pretty compelling stuff. The election this year is an entertainment option."

Bock concurs, pointing to provocative nightly newscasts, heated presidential debates with record viewership and must-see political skits on Saturday Night Live as having an impact — not to mention the unpredictability of Republican candidate Trump.

"Everything that comes out of Donald Trump's mouth is entertaining enough to at least compete with seeing Ben Affleck in The Accountant," says Bock.

The current environment could present a challenge for upcoming offerings such as Jack Reacher: Never Go Back (in theaters Oct. 21), with Tom Cruise reprising his role in the action sequel, and Inferno (Oct. 28), the latest Dan Brown mystery thriller starring Tom Hanks.

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The Nov. 4 weekend should provide a box-office boost with Benedict Cumberbatch appearing as Marvel's Doctor Strange and the animated Trolls stepping up.

"We need a box-office superhero this fall, and Doctor Strange could be just that," says Dergarabedian.