Imports, which are a subtraction in the calculation of GDP, also decreased.

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They do so by starting chain-reactions that result in the addition and subtraction of molecular sub-units known as phosphate groups from particular proteins in the nerve cell being stimulated.

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But that was a "very crude calculation, " Mr. Tombs says in an interview, based on the subtraction of one work day's output, or about 1.5% of the quarter's total, from the calendar.

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Accounting for this subtraction, fewer onshore acres were leased in 2009 than any other year on record.

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In product design, business strategy, and yes, communications and presentations, subtraction often adds value.

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House construction is counted in GDP as a percentage of the median selling price at the time of the start, exaggerating the subtraction when prices are falling along with volumes.

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