For a fixed monthly fee, homeowners can sign up for solar energy as a service from companies like Solar City, SunRun, or Sungevity.

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One of the biggest tail risks, Garthwaite says, is a eurozone break-up, something investors have been worrying about as the debt crisis shows no sign of abating or being fixed quickly.

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The thick blast doors on the entrance to the Inverurie complex were permanently fixed in an open position in 1992, a clear sign at the time of the relaxation in tensions between the East and West.

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Customers sign up to a 12 month plan at a fixed monthly price.

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As the oldest son, Tagg Romney commandeered the way-back of the wagon, keeping his eyes fixed out the rear window, where he glimpsed the first sign of trouble.

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Fixed investment, which is about 12% of GDP, shows a very modest sign of recovery and still stands nearly 22% below its peak level nine quarters ago.

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Bond prices fell after the report, but that could be a positive sign, indicating investors were looking for better returns from a growing economy than they could get in the fixed-income market.

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