The fact of the matter is, human behavior is too complicated to limit to just one simple factor or another.

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The falling share who itemize could be a factor as Congress considers whether to limit itemized tax deductions as part of a tax reform.

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But that last factor aside, there is no obvious limit to consolidation currently in sight, only supply and demand.

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U. will continue to be a significant factor in China growth, and will surely limit prospects for any revival in Chinese exports to Europe this year.

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The stronger U.S. dollar index is a major bearish factor for the precious metals markets and did limit buying interest not only in gold and silver Thursday, but also across the entire raw commodity spectrum.

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This worst-case scenario doesn't factor in hedging strategies the banks might have taken to limit these risks.

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In 2004 he quit Pop Idol, effectively killing it, and launched The X Factor, an audition show featuring groups and individual singers with no age limit.

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And when you throw in the fluctuations of eight or nine opponents' cards--including no-limit showdowns in which two or more players have very strong hands--the luck factor becomes practically decisive.

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And the third factor, of course, is the price of fuel, which seems to know no upward limit these days.

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