If you’re middle-aged and miserable, don’t despair: Give it a decade or two and you’ll be feeling like a carefree young person again.

如果你现在身处中年，迷惘痛苦，千万不要绝望：再等一二十年，你就又会像年轻人一样无忧无虑了。

Researchers have revealed that life satisfaction peaks at 23 and 69. People in their early twenties overestimate their future life satisfaction by an average of around 10 per cent, before the disappointments of life kick in.

研究人员发现，人在23岁和69岁时的生活满意数值达到点。在令人失望的生活到来之前，平均大约有10%的人会在二十出头时对未来生活的满意程度过于乐观。

They face decades of declining expectation before hitting their lowest point in their mid-fifties, when regrets over unrealised dreams are at their greatest. Satisfaction levels finally start to rise again after 55 and peak once more at 69, according to a study by the Centre for Economic Performance at the London School of Economics.

伦敦政经学院经济表现研究中心的调查表明，此后几十年中，人们对生活的期望会越来越低，直至五十五岁左右时满意度降到点。这时，他们会后悔没有在自己状态的时候实现曾经的梦想。但过了55岁，满意度曲线又会重新上升，在69岁时重回状态。

Those aged 68 underestimate their future happiness by 4.5 per cent, meaning they no longer face disappointment, the researchers found. The findings suggest that actresses Emma Watson and Kristen Stewart, both 23, should relish this year.

研究发现，只有4.5%的人到68岁时会低估他们的幸福程度，这意味着他们不再感到失望。根据这个研究，两位23岁的女演员艾玛·沃森和克里斯汀·斯图尔特都应该好好享受这一年。

If the research is borne out they will be optimistic but are likely to face disappointment in the next four decades. Previous studies have found that human contentment follows a U-shaped pattern, with those in their early twenties and the retired ranking highest.

如果该研究正确，那接下来40年里即使她们保持乐观心态，也更有可能遇到令人沮丧的事情。之前有研究显示，人们的幸福程度呈U形曲线状，刚刚二十几岁的年轻人和退休老人的幸福程度。

The pattern has been observed in more than 50 nations and across class and financial divides. And a study by the National Academy of Sciences in the US found evidence that even great apes can suffer a mid-life crisis.

这一曲线在50多个国家都适用，而且不分阶级、不分经济情况。美国国家科学院甚至发现就连高等类人猿也会受到“中年危机”的影响。

The CEP paper, to be published this week, is the first to examine how our expectations compare to reality at different life stages. Researcher Hannes Schwandt, 30, analysed happiness levels for 23,161 Germans aged 17 to 85.

经济表现研究中心的论文将于本周发表，这是份以人类现实年龄和理想生活预期作对比的研究报告。为此，30岁的研究者汉内斯·施瓦德调查了23161名17至85岁的德国人的幸福程度。

Dr Schwandt, who is based at Princeton University in the US but is a visiting researcher at the London centre, said: ‘One theory is that the U-shape is driven by unmet aspirations which are painfully felt in midlife but beneficially abandoned later in life.

施瓦德博士本在美国普林斯顿大学工作，现在在伦敦客座研究员。他说：“有一种理论称，无法满足的欲望催生了U形曲线，这种痛苦在中年时期尤为强烈，但随着人慢慢变老，放弃一些追求，便又重新快乐起来了。”

‘People in their fifties could learn from the elderly, who generally feel less regret. They should try not to be frustrated by their unmet expectations because they are probably not feeling much worse than their peers.’

“五十多岁的人应该向比他们更老的人学习，大部分老人都不会后悔太多事情。不要因为没有达到预期而沮丧不安，因为他们的同龄人大概也处于相同状态。”