The IEA uses a complex calculation called the carbon intensity index to show how much CO2 is emitted to provide a given unit of energy.

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It's a complex calculation, says Financial Engines' Mr. Jones.

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On one page there was a complex mathematical calculation of how fast each cell tower could carry data.

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Rather than 50% of the normal fare it currently receives, a "complex" calculation approved by the Department for Transport will be used.

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Changing the figure to take account of the cycle would make more sense, but it would introduce a complex and disputable new calculation, with countries arguing endlessly over precisely where they were in the cycle.

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The calculation of scores was complex: Not only were there two tests, but students' scores depended on their precise ages.

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The cold calculation of national interests is a complex business, as any student of game theory can tell you.

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That makes them well suited for complex tasks in which the answer to one calculation is used to work out the next.

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Of course the logic behind the new calculation comes after the financial crisis when the value of homes plummeted, and homeowners had meanwhile invested in complex securities that, in many cases, had dropped in value as well.

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