The wage gap between rich and poor countries is far wider than it was a century ago, during the great age of migration from Europe to America.

ECONOMIST: Migration

The line marked old age structure assumes net migration of 140, 000 but with higher life expectancy and lower fertility.

BBC: England and Wales population up

Young age structure combines high migration with lower life expectancy and higher fertility.

BBC: England and Wales population up

For example, some evidence hints at extensive migration into Europe after the last Ice Age.

BBC: Fossil human traces line to modern Asians

But it is possible, at least, that this decline of lifespans in certain areas, and increasing gap in age at death, is explained purely and solely by migration of the elderly.

FORBES: Life Expectancy Is Falling For U.S. Women

Born in the capital of the old Confederacy, brought north by her parents as part of that great migration, Dr. Height was raised in another age, in a different America, beyond the experience of many.

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And musicians come to hear the age-old songs with fifteen-syllable lines and themes of migration and survival.

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In its annual report to ministers, it said in the medium term "higher inward migration would tend to increase tax receipts and not add much to age-related spending pressures, even whilst allowing for an increase in GDP from extra employment".

BBC: England and Wales population up

The success of retailers such as the dedicated online fashion site Asos hints at how rapid the migration of sales from traditional stores to the internet is, especially among the 18-34 age group.

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