Singapore's "Gini coefficient" the best-known economic measure of income disparity is the second highest in the developed world.

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Taking into account the existence of hidden income, the Gini coefficient of household income distribution is remarkably higher than the 0.47-0.50 calculated by different experts.

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America's Gini coefficient has risen from 0.34 in the 1980s to 0.38 in the mid-2000s.

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One thing they all have in common is that their income inequality, as measured by the Gini coefficient, is well below that of the US. In fact, the Scandinavian and German-speaking countries that consistently score well on a variety of business and quality-of-life surveys have some of the lowest inequality scores among developed nations.

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