It's one of the mysteries of accounting at the Hollywood studios, as we have watched budgets balloon bigger and bigger for decades - how do they make money from their films? Grosses of the biggest hits may be up at well, thanks to inflation, but the ratio of dollars spent to dollars earned just gets smaller and smaller.
Titanic and Avatar style grosses were the norm during the days of the original Star Wars trilogy, the Bruckheimer /Simpson films of the 1980's - where your films would gross $10-15 dollars for every dollar you spent. (The first Star Wars and E.T. - they returned about $40 dollars for every dollar spent in their budget.) Now, grossing as little as $2-3 dollars for every dollar you spend can get you declared a blockbuster hit; the average Harry Potter film grossed $4-10 dollars for every dollar spent on them. Are there just that many more platforms to get revenues from films? From DVDs to Blu-rays to direct downloads to your personal iPad etc? The days of networks spending big money to get the TV premiere of a film; that doesn't exist anymore.
Or have the studios just isolated themselves successfully by being part of larger media empires, where dollars can be spread around creatively? Disney made a financial declaration on John Carter because it was the end of a financial quarter and they had to report to their board. They guessed at an estimate because corporate protocol demanded they do. But they are a mega corporation of theme parks, TV station ownership, toy company and film production house. Who knows how they truly evaluate success.
The days when a single film can sink a studio (like Heaven's Gate did to United Artists) seem to be a thing of the past, with all the layers studios have added to their production mechanisms. It's also unfortunately led to a lack of creative risk-taking for the most part, as we are bombarded with more remakes and sequels.
John Carter, at least, was more creative risk taking than the average mega project. Like Peter Travers of Rolling Stone observed, it is actually admirable it's not a project of cynicism, but trying to go back to giving audiences a sense of retro, old style wonder.