The most important factor slowing the out-migration of Californians in 2008 to 2011 was that home prices fell more in California than in the U.S. overall, making California more affordable relative to the rest of the country than during the housing bubble.

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One factor, he says, could be slowing production ahead of what he expects will be a September quarter launch of the iPhone 5S. But he adds that he thinks the effect from pending launches is minor, and that most of the slowing production reflects softening demand.

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