One of its long-term partners, Google, has a search deal with Mozilla that is renewed every two or three years.

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The poverty numbers are derived from a household survey, known as Casen, conducted by the government every two or three years.

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Most were trained as generalists, rotating through the company's departments every two or three years, which means they know a little about everything.

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United usually replaced its 15, 000 PCs every two or three years.

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Every two or three years, the company hands out a survey that, among others things, asks employees how well the company is fulfilling its own corporate vision.

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Moreover, guidelines from the American Dental Association state that healthy adults should have a bitewing X-ray no more than once every two or three years, and that there is little reason to X-ray patients who do not have symptoms.

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Normally, those conditions occur two or three times every 10 years.

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Life expectancy has been rising by two or three years for every ten that pass, despite repeated forecasts that it was about to reach its limit.

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It used to be that we were replacing our business computers every two to three years, oftentimes around a release of Windows or just from frustration.

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