"Jurassic World" was without a doubt the biggest hit of the summer of 2015 with a record U.S. opening of $208.8 million.
Among those surprised by the monster payday were the box office analysts who projected "World" to make $120 million.
"World" wasn't alone in perplexing those who predict how much a movie is expected to make in North America.
Disney's "Avengers: Age of Ultron" opened to $191.3 million in May, but that total seemed small compared to the near $220 million it was projected to make. The opposite was true for Universal's "Straight Outta Compton" which was predicted to make only $25 million for its debut last weekend, but instead went on to make $60.2 million.
The analysts who predict how big a movie will be weren't always wrong this summer. They were on the money for "Minions," "Pixels," and "Tomorrowland." But more often than not this summer, their guessestimates were off.
"I kind of wish we didn't even do projections," said Paul Dergarabedian, a box office analyst for Rentrak (RENT). "It's a crapshoot, and it works better if everyone just waited until Sunday."
There are reasons they try to determine how much a movie will make.
"Hollywood is just like any other business. There's a lot of value in figuring out how something is going to perform beforehand," said Phil Contrino, chief box office analyst at BoxOffice.com.
If a movie is projected to be a blockbuster, theater owners will most likely staff up in order to handle the influx of moviegoers.
Related: The four big winners of the summer box office
Box office projections could also impact the marketing of a film heading to its debut weekend.
"If a studio looks at research and feels like a film is not hitting, the studio can proactively expand its marketing to make sure that it connects with specific audiences in a big way," Contrino said.
As far as how projections are made, some analysts say that it can be a mix of industry talk, historical perspective, and gut instincts.
However, social media more so than anything else has become the most important barometer of a film's potential success.
This is done by watching Twitter to see if a film's tweets are seen as positive or negative and what kind of buzz is surrounding the film on sites like Facebook and Snapchat.
"If we didn't have social media, 'Jurassic World' would have probably been closer to that $120 million," Dergarabedian said. "In the past, you had a few critics telling you what to see. Now, we have millions of people on social media telling you."
Related: How Universal went from fifth to first the box office
And the viral power of social media has made movie projections more volatile.
"What we're seeing now is a shift in how quickly buzz builds with audiences," Contrino said. "Once a film opens on Thursday all bets are off no matter how it looked on paper."
"Projections create certain expectations, but word of mouth can make a movie special," Contrino added.
