"The Avengers" brought in big bucks on the big screen, and raunchy comedy "Ted" broke out as a surprise hit. But alongside the summer successes came a number of flops. After six consecutive increases, summer ticket sales in the United States and Canada are running 5 percent behind last year's record, according to the box office division of Hollywood.com.

The recent slide dragged down a year that raced to a fast start and had studio executives salivating over the prospects of even bigger bonanza during the summer, a season that accounts for 40 percent of yearly box office.

This year, it was a summer of extremes. Big blockbusters such as the Batman film "The Dark Knight Rises" performed well while films such as the Adam Sandler comedy "That's My Boy" did not match industry expectations.

Despite the summer results, studio executives stressed, domestic box office sales since January are higher than at the same point a year ago.

Summer sales suffered from competition from the Olympics, which drew record TV ratings, and nervousness after a mass killing at a "Dark Knight Rises" premiere in Colorado, studio executives and industry analysts said.

Domestic receipts for "Dark Knight Rises" reached $422 million through Sunday, making it the year's No. 2 film behind "Avengers." "It's a strong result given the circumstances," said Jeff Goldstein, executive vice president of theatrical distribution for Warner Bros., a unit of Time Warner Inc.

But with just one summer movie weekend remaining, overall domestic sales will fail to pull even with last year's $4.4 billion record, according to Paul Dergarabedian, president of the box office division of Hollywood.com. As of Sunday, the summer tally stood at $4.0 billion. The last time summer sales decreased from one year to the next was from 2004 to 2005.

"We have seen most films weaker than expected," said Tony Wible, industry analyst for Janney Montgomery Scott. "A fewer number of films accounted for the upside."

Early in the year, movies such as Universal's Denzel Washington thriller "Safe House" and Sony's Channing Tatum romance "The Vow" blew past their modest forecasts. "The Hunger Games," from Lions Gate Entertainment, exploded as Hollywood's next big franchise.

Through April 30, North American (U.S. and Canadian) sales towered 14 percent above year-earlier levels, according to Hollywood.com.

The summer movie season, measured by Hollywood from May through Labor Day in September, kicked off with a record-breaking $207 million opening weekend for Walt Disney Co's superhero mash-up "Avengers."

But after a string of films like Universal's big-budget "Battleship" and Warner Bros.' horror film "Dark Shadows" failed to meet industry forecasts, domestic year-to-date sales were just 4 percent above 2011 at $7.4 billion, Hollywood.com figures show.

So far this summer, 11 movies have sold more than $100 million worth of tickets, below the 18 that reached that mark last summer.

Still, Hollywood is encouraged by the summer's big hits and the year-to-date gains. "Right now, the industry as a whole is up. That's a positive," said Nikki Rocco, president of domestic distribution for Universal, a unit of Comcast Corp.

Some well-known franchises performed as well as expected, including Sony's "The Amazing Spider-Man," and Disney's Pixar studio added another movie, "Brave," to its stable of hit films. And there was the annual summer surprise: Universal's "Ted," the $50 million story of a foul-mouthed, pot-smoking teddy bear, pulled in a surprising $215 million at domestic theaters.

Hollywood was less successful remaking older offerings. Sony's sci-fi remake "Total Recall" bombed while Johnny Depp failed to lure theater goers to "Dark Shadows," a loose remake of the 1960s soap opera.

Studios also struggled to replicate last year's success with adult comedies such as "Bridesmaids" and "Bad Teacher." Fox's "The Watch," with heavyweights Ben Stiller, Vince Vaughn and Jonah Hill, fell flat. Adam Sandler had his weakest opening weekend in 16 years with "That's My Boy."

"You can't just count on blockbuster superheroes and action movies alone," said Hollywood.com's Dergarabedian. Studios also need comedies and adult dramas to post record summer results, he said.

Hollywood often says box office swings are based simply on the appeal of films. This summer, moviegoers may have become more discerning when deciding where to spend their entertainment dollars, executives said.

"I don't think you can fool audiences," Universal's Rocco said. "They are savvy, and expectations are high."

Many films are sailing past the weaker domestic box office with huge performances overseas. Animated sequel "Ice Age: Continental Drift" from 20th Century Fox hauled in $665 million from international markets, four times the $154 million in the United States and Canada.

"Battleship" grabbed $237 million abroad, compared with $65 million in the domestic market.

Executives are optimistic the year will finish strong with big holiday releases such as the finale in the "Twilight" vampire series, James Bond movie "Skyfall" and fantasy "The Hobbit," the first in a trilogy set 60 years before the "Lord of the Rings" blockbuster movies.

When Hollywood looks back on 2012, "I think everyone is going to be quite pleased with the success," said Rory Bruer, president of distribution at Sony's film studio. "It's turning out to be one of our biggest years ever, both domestically and internationally."

(Reporting By Lisa Richwine; Edited by Ronald Grover and Steve Orlofsky)

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