And a licence fee to enter a market is most definitely a sunk cost.

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For the Jets, the 2013 off-season will be about whether they recognize the old economics idiom that sunk cost are sunk.

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It's a sunk cost, and I should stop worrying about it.

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Think of the debt as a sunk cost (I am reminded of all those nuclear reactors that weighed down utility stocks in the 1980s and 1990s).

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The key to our business was getting large initial orders from a customer and cashing their check quickly so the customer viewed their investment as sunk cost.

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Disruptive technology and smart investing tell us that yesterday is a sunk cost and it is all about logically, and creatively, assessing the value of the future.

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Each of these companies has a created an operating system that people invest their time and money in, systems that value the sunk cost in both time and money and penalize the long slog of moving to another digital planet.

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You can survive the arrival of me-too generic competitors: They put an end to your sunk-cost recovery only after the patent expires.

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Governing from the hard left sunk Democrats in 2010 and would cost them again in 2014.

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If the plan has the desired effect, some of this cost will have been sunk before the government pops the question, perhaps tipping a few voters in favour.

ECONOMIST: The single currency