So the increase of 12 years in maximum life expectancy during the 20th century was just one-third as large as the increase in average life expectancy during the period (36 years).

因此，20世纪最长寿命12年的增长幅度只不过是同期平均寿命增幅(36年)的三分之一。

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Although seven out of 10 early 50-somethings quizzed for the survey defined themselves as middle-aged, the average age at which the period of life was perceived to start was 54 years and 347 days old.

BBC: Middle age begins at 55 years, survey suggests

Women and anyone else with an above average life expectancy tend to do better because they typically collect benefits for a longer period of time.

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