There are no reliable estimates of the net effect of migration on the South African economy.

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But the slowed migration has significant political effect.

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An issue that ought to arise at the FORBES GLOBAL CEO Conference on Sept. 24-26 in Hong Kong is the effect of extraordinary migration levels in recent decades.

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It's difficult to show a perfect cause-and-effect relationship when it comes to migration patterns, as individuals and families move for a wide range of reasons.

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State media said the move, to come into effect on 14 January next year, would "update" migration laws to reflect current and future circumstances.

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