Box Office: May Total Down 12 Percent Despite 'Amazing Spider-Man 2,' 'Godzilla'

Sony Pictures

Revenue topped out at $1.008 billion, the lowest level since 2010.

Where's Iron Man when you need him?

North American box-office revenue for the month of May -- the start of the all-hallowed summer season -- tumbled a steep 11.7 percent over last year, diminishing gains made in the winter and spring.

According to Rentrak, revenue topped out at $1.008 billion, the lowest level since 2010. Revenue clocked in a record $1.414 billion in May 2013, when Iron Man 3 earned an outstanding $379 million for the month on its way to topping out at  $409 million domestically. Revenue hit $1.025 billion in 2012 and $1.037 billion in 2011, but only $914.4 million in 2010.

May's decline over the same period in 2012 and 2011 was far less dramatic, with revenue down 1.7 percent and 2.8 percent, respectively. And May 2014 was up more than 10 percent over 2010.

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The Amazing Spider-Man 2, which, like Iron Man 3, debuted over the first weekend of May, failed to crack $200 million for the month.

The Sony sequel recorded revenue of $193.1 million in May, followed by Legendary and Warner Bros.' Godzilla with $171 million (Godzilla debuted May 16). Both films suffered steep drops in their second weekends, muting their overall performances.

The first Amazing Spider Man, released in July 2012, earned $262 million domestically. While the sequel is still in theaters (ditto for Godzilla), it will likely top out at roughly $220 million domestically.

Disney's Maleficent and Fox's X-Men: Days of Future Past are still early in their runs -- particularly Maleficent. Days of Future Past, hitting theaters on May 23, earned $152.7 million for the month. Maleficent, opening over the weekend of May 30 to June 1, opened to $69.4 million.

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May brought several high-profile disappointments, including the Adam Sandler and Drew Barrymore comedy Blended, which has only grossed $29.4 million, and Seth MacFarlane's A Million Ways to Die in the West. The R-rated Western comedy, opening opposite Maleficent, debuted to a paltry $16.8 million.

Not every comedy turned sour. Seth Rogen and Zac Efron's R-rated comedy Neighbors was a surprise hit, taking in a stellar $126.8 million for the month (Universal released both Neighbors and Millions Ways to Die).

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Box-office revenue year to date is still up over the same period in 2013 by 2.6 percent, although that number was higher heading into summer. January revenue was up more than 8 percent, followed by a 13.4 percent jump in February. March was down 2.8 percent, while April revenue soared more than 21.5 percent over 2013.

May revenue figures include holdover titles, such as 2014 April releases Captain America: The Winter Soldier, The Other Woman and Heaven Is For Real.