The North American box office is on pace to set an all-time record this year and this summer is already outpacing last year’s $4.1 billion tally by a significant margin, with Rentrak forecasting a $4.4 billion total by Labor Day.

But not everyone is basking in the box office glow. In fact, just two Hollywood studios — Universal and Disney — so far account for a whopping 61 percent of domestic ticket sales since the first Friday of May, according to Rentrak.

And for the full year, the two studios claim seven of the 10 highest-grossing movies, including Universal’s $638 million-grossing “Jurassic World.”

That’s bad news for the execs at Warner Bros., Fox, Paramount and Sony — who have struggled to produce hits through what is traditionally the busiest moviegoing season of the year.

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Universal is enjoying one of the greatest years in Hollywood history, racking up $2.04 billion in domestic grosses so far in 2015 — setting a new standard in record time.

“Furious 7” and “Jurassic World” have topped $1 billion globally, while Illumination Enterainment’s animated hit “Minions” is expected to break the 10-figure barrier when it opens in China next month.

Disney is close behind, claiming 26 percent of the summer box office thanks largely to releases from Pixar Animation and Marvel, which have helped the studio churn out hits like “Avengers: Age of Ultron,” “Inside Out” and “Ant-Man.”

“Ultimately, it comes down to the content — the slate of films in the particular timeframe that makes all the difference,” Rentrak senior media analyst Paul Dergarabedian told TheWrap. “If you have the goods and moviegoers respond, then you can have a year like the studios at the top of the chart.”

Still, Dergarabedian noted that market shares are likely to shift from season to season and year to year. “It’s the nature of this very cyclical, content-driven business,” he said.

Executives at Fox can attest to that. The studio is coming off a record-breaking 2014, but this year it’s languishing in fourth for the year. Its share of the summer box office is just 7 percent. And the $120 million superhero reboot “Fantastic Four” looks like one of the season’s biggest flops.

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Warner Bros. is in third place for the summer, with about 14 percent of the market. The studio has had hits like Dwayne “The Rock” Johnson’s earthquake epic “San Andreas” and “Mad Max: Fury Road,” which reignited a dormant franchise. But “Magic Mike XXL,” “Vacation,” “Hot Pursuit,” “Entourage” and “The Gallows” all missed the mark, and this month’s $75 million “Man From U.N.C.L.E.” is shaping up to be a costly bomb.

Over the year, Warner has released 17 movies — far more than Universal’s 12 and Disney’s eight. It’s telling that the studio’s highest-grossing film is “American Sniper,” which was a 2014 release.

Paramount had just two summer releases. Tom Cruise’s “Mission: Impossible – Rogue Nation” delivered, but Arnold Schwarzenegger and “Terminator: Genysis” did not, raising doubts about that franchise’s future.

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Sony Pictures is still struggling to find its footing in the wake of last fall’s computer hack and the replacement of Amy Pascal as co-chairman with Tom Rothman. The studio’s summer fare included the Bradley Cooper-Emma Stone romantic comedy “Aloha,” which seriously misfired at the box office, and its lone tentpole, “Pixels,” an Adam Sandler-Kevin James CG adventure that cost roughly $90 million and has grossed $64 million domestically. That’s less than James’ more modestly budgeted spring comedy, “Paul Blart: Mall Cop 2.”

Meanwhile, Lionsgate rolls out the Kristen Stewart-Jesse Eisenberg action comedy “American Ultra” this weekend, but its only other summer release was the claymation kids film “Shaun the Sheep.” The British import is a critical darling, with an astonishing 99 percent positive ranking on Rotten Tomatoes, but it’s brought in less than $12 million in the U.S.