Not even the combined heat of the Avengers, Melissa McCarthy and the Barden Bellas can push the summer box office past the boiling point.

Take this weekend when “Spy,” a critically adored espionage send-up with McCarthy, bowed to a solid $30 million, even as overall ticket sales declined for the third time in a row. That losing streak comes on the heels of the worst Memorial Day the movie business has seen in five years as “Tomorrowland,” the heavily promoted George Clooney fantasy, stumbled out of the gate.

There’s still a lot of popcorn movie season left to go, but this was not the way that many analysts and studios expected summer 2015 to play out.

“It’s not a Chicken Little, ‘the sky is falling’ situation, but certainly we need a big hit and we need it now,” said Paul Dergarabedian, senior media analyst at Rentrak.

The problem is that too many movies have arrived without numerals in the title or have been pitched to older audiences instead of the teenagers who drive the movie business from May through August.

“A lot of original titles combined with R-rated fare has had an impact,” said Dergarabedian.

There are a couple of reasons the expected windfall has yet to materialize. “Avengers: Age of Ultron” has earned a massive $438 million Stateside, but it will fall short of the $623 million that its predecessor racked up. And films like “Mad Max: Fury Road” have failed to match the big box office returns of “Maleficent” and “X-Men: Days of Future Past,” both of which premiered early in the summer of 2014.

As it currently stands, 2015’s summer is outpacing the previous year’s ticket sales by a mere 2.9%. That’s a paltry lead given that 2014 fielded the worst summer since 1997 when adjusting for inflation.

Help is on the way. “Jurassic World” is projected to open to north of $100 million and the months of June and July bring such highly anticipated releases as “Minions,” a spin-off of “Despicable Me”; Pixar’s “Inside Out”; the fifth “Mission: Impossible”; follow-ups to “Magic Mike” and “Ted”; Marvel’s “Ant-Man”; and the gaming comedy “Pixels.” On paper, they look like winners.

Phil Contrino, VP and chief analyst of BoxOffice.com, says scheduling is to blame. The picture might seem rosier if, say, “Mad Max: Fury Road” and “Pitch Perfect 2” had debuted over Memorial Day instead of “Tomorrowland,” he argues, and the rest of the warm months will see an impressive number of sequels and reboots with sizzle.

“There’s no reason to panic at all,” said Contrino. “Some of the strongest movies of the summer are still on the horizon. June and July were pretty weak last year, but this year is much stronger.”

It’s also true that individual movies are hits whether or not the overall box office is booming. “Spy” may have generated less than the $35 million that many analysts had expected it would open with, but with a production budget of $65 million and strong overseas numbers, it stands to be profitable. Likewise, “Pitch Perfect 2,” “Avengers: Age of Ultron” and “San Andreas” will enrich their backers, even if the larger business is struggling.

With the domestic box office a diminishing part of a film’s revenue pie, U.S. audiences aren’t as important as they were a decade ago. “Avengers: Age of Ultron,” for instance, has generated 67% of its $1.3 billion bounty from foreign markets, while “Mad Max: Fury Road’s” best chance at recouping its $150 million production budget lies with how fervently overseas crowds embrace its apocalyptic vision.

The issue is one of perception, however, and it’s a predicament largely of Hollywood’s own making. Facing a bleak 2014, studios and exhibitors relentlessly beat the drum for 2015, predicting that records would shatter and old benchmarks would be left in the dust. Some analysts even projected that summer 2015 would be the first time in history that North American receipts would top $5 billion.

That now seems unlikely. Ticket sales trail previous record holder, the summer of 2013, by 7% and some analysts are revising their summer estimates downward to roughly $4.5 billion, less than the high-water mark of $4.8 billion.

“The summer just isn’t firing on all cylinders,” said Jeff Bock, box office analyst with Exhibitor Relations. “Four out of six weekends this summer have been down and that’s left a sour taste.”

Of course, next weekend, when “Jurassic World” takes multiplexes by storm, the seasonal depression could give way to euphoria. Such is life on the emotional roller coaster that is the summer box office.