Faced with a high minimum wage, shop owners would be sure to look for ways of keeping costs down by firing people, or by squeezing differentials as far as they dare.

ECONOMIST: The minimum wage

Regulators cracked down on some specialists two years ago, accusing them of improperly stepping ahead of client orders and benefiting by minor price differentials.

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Germany's system of centralised pay bargaining, under which unions and bosses set wages and hours across whole industries, makes matters worse by compressing wage differentials.

ECONOMIST: Wirtschaftsblunder

In the announcement, the government said that the duty hikes were needed to ease price differentials caused by the ever weakening global economic outlook.

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Such price differentials are arbitraged by Internet brokers, and, like all modern markets, it's a fast-shifting business.

FORBES: On The Cover/Top Stories

Suppose a high minimum wage, by pressing on the structure of pay differentials, raises wage growth and hence inflation across the economy.

ECONOMIST: Economics focus

The mighty dollar is supported by risk aversion and economic recovery, while the EUR remains vulnerable to Eurozone contraction and rate differentials favoring U.S. Treasury securities.

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