But the difference between gross ticket sales, gross earnings and net earnings is ignored.

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Industry insiders point out that top rock acts can take home 50% or more of gross ticket sales after production costs.

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Gongaware wrote to his boss, AEG Live President Randy Phillips, that they should present gross ticket sales numbers to Jackson, not the percentage of the net profits, during contract talks.

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Often toting nothing more than a USB stick and a pair of Pioneer CDJs, their production costs are often negligible, unlike rockers and pop stars who typically take home just one-third of gross ticket sales.

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With the exception of Spain and Italy, the two countries hit the worst by the economic downturn, 2011 was a record high year for gross box office movie ticket sales despite the increasing number of legal streaming and rental VOD offers online.

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Seventy percent of the first weekend gross for Alice in Wonderland came from 3-D ticket sales, 68% for How to Train Your Dragon and 60% for Toy Story 3, according to BTIG Research (subscription required to follow the link).

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First, we halved the box office of each film (to approximate the studio's share of ticket sales) and added those numbers to calculate gross box office.

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The studios also are regularly rolling ticket sales from the additional screenings into the next day, giving them an opening-day gross that includes more than 24 hours of business.

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