The unemployment rate has dropped more than 40% of the way back to its pre-recession level, but the employment-to-population ratio is closer to its trough than its pre-recession peak.

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While the city population has shrunk (from a peak population of 1.8 million in 1950 to 714, 000 in the last census), it has hardly reduced the government that serves it.

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It isn't clear how much demand there would be for his planned 800, 000 square feet of office space in the Rust Belt city that has seen its population fall to 198, 000 from its peak of 290, 000 in 1960.

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The sea lion population seems to have rebounded all the way to its natural peak.

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Development groups are nervous about attempts to define a hierarchy of global problems with population at the peak.

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From its peak in the mid-1970s, the ratio of oil revenue to population moved against Venezuela, partly because migrants flooded in from poorer neighbouring countries.

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However, the employment-population ratio reached its most recent peak of 63.4% in December 2006, and then began to decline.

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The Scottish population had been falling steadily from a peak of 5, 227, 000 in the mid-1970s to 5, 055, 000 in 2002, but has been rising since.

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There is no explicit population target, but the latest forecasts suggest that numbers will keep growing from about 1.3 billion now to a peak of around 1.46 billion by 2030 and then start declining gently.

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