Moviegoers have always loved seeing Leonardo DiCaprio sporting period costumes, just so long as it's not a fat suit. But as eye-popping as this weekend's box-office results were for "The Great Gatsby," not that many moviegoers felt compelled to watch DiCaprio don a tux or strut his stuff wearing a pink suit in the 3-D format.

Only 33% of "Gatsby's" $51.1-million weekend gross came from 3-D showings, a cut considerably less than what action-adventure spectacles typically make. (By comparison, 3-D receipts for "Iron Man 3" accounted for 46% of its opening-day grosses.)

Does this mean that audiences resisted director Baz Luhrmann's high-tech approach to classic literature, feeling, as Stephen Colbert put it the other night, that "it's like your homework coming right at you."

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Not necessarily. A closer look at the weekend's numbers shows that younger audiences embraced the movie and its 3-D format more than members of Colbert's book club. Though "Gatsby" graded out to an OK B on CinemaScore, the 35-and-under crowd gave the movie a B+ and the 18-and-under gang liked it even more, assigning it an A-.

"The younger we play, the bigger the 3-D numbers are," says Warner Bros.' Dan Fellman, president, domestic distribution. "That's only going to build."

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Moreover, says Hollywood.com box-office analyst Paul Dergarabedian, the fact that the movie performed so well commercially can be considered a victory for Luhrmann's decision to shoot it in 3-D. Had the film bombed, he says, the failure could have been blamed on the format.

"Positive word of mouth propelled the film to a bigger-than-expected debut in both 2-D and 3-D formats, with the 3-D offering a notable marketing peg that had people debating the appropriate use of 3-D," Dergarabedian says. "It opens up the notion of 3-D as a viable option for even character-driven period-style films like 'Gatsby.' "

That option won't be present for DiCaprio's next movie, Martin Scorsese's biographical crime drama "The Wolf of Wall Street," due in November.