He argues that African economies must move away from dependence on a single commodity.

ECONOMIST: Zambian copper

Using inedible inputs avoids fights about diverting food crops for fuel, and frees the industry from reliance on a single commodity.

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To earn the foreign exchange needed to pay for imports and to service debts, reliance on a single commodity (like Zambia's copper) is just too risky.

ECONOMIST: Zambian copper

Whether it be copper in Chile, oil in Venezuela, soybeans in Paraguay or tourism in the Caribbean, too many countries are overly reliant on a single commodity or industry.

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Other countries riding high today because of good prices for a single commodity, such as Botswana, which is doing well from diamonds, should stimulate new, competitive industries, such as tourism.

ECONOMIST: Zambian copper

Their trade had thrived under restrictive gold-control laws that had been in place since the late 1930s, when gold became the single largest commodity to be smuggled into India.

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By restricting government support to a single identical plan, it forces insurance companies offering the Basic Plan to compete to sell a uniform commodity, which will make competition really thrive.

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