The magazine worked out that the new private centres had done only 59% of the average annual number of operations they are expected to carry out.

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However, the increased productivity levels suggest it will require higher average annual GDP growth to generate the same number of jobs enjoyed during those years.

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This number is calculated by simply taking an average of annual returns over a given period.

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That number is paltry compared to the average U.S. annual growth rate of 2.8 percent since 1973 and is below the 2.5 percent long-term economic growth rate typically used by financial markets to value businesses.

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The annual report found that the number of people living with incomes below half the national average remained at approximately 10.7m.

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The number ranked excellent in the annual Good Beach Guide has again fallen below the UK average.

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Its 30% average annual growth over the last five years is directly attributable to its ties with Cordis, good enough to become number 24 on our list.

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To compose the list, Rent.com looked at the number of married couples, the percentage of families with children under the age of six, average annual income, cost of living, and rental availability in 25 of the largest U.S. metro areas, using data from the Bureau of Labor Statistics and the Census Bureau.

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