Population migration rates and net migration rate have relatively clear role on guidance, population migration can be considered the external guidance to the information flow of mobile communication;

人口迁入率和净迁移率的导引作用相对明显，人口迁移可以认为是对移动通信信息流动的外部导引；

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Only Detroit has a higher net migration rate among the 200 largest U.S. metros.

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As Calderon recently noted in The Wall Street Journal, the net rate of migration of Mexican workers toward the United States has recently been zero.

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