That midlife slump (not to be confused with a midlife crisis) is often nothing - just a natural transition due to the passing of time.
Those likely to notice it are people that seem to have everything going for them; they're achieving their goals, and nothing much changed, yet they feel less satisfied than they expected and think there must be something wrong with their lives.

The midlife slump

There is a huge amount of untapped wisdom and potential in older people.
Because of the happiness curve, they are often in a position where they desire to give back by being mentors, volunteers, or work easier jobs, which allow them to use their skills.

Untapped wisdom

When we are young, we are often over-optimistic about the satisfaction we will gain out of our future successes. With age, as our ambition drives us to more, we don't feel the satisfaction we expected, so we wonder if there's something wrong with us.
It is only once we realize that our values change with age - in that we savor other simpler pursuits such as relationships, a hobby, or volunteer work - that we gain satisfaction.

Values change with age

There is increasing evidence that happiness through adulthood is U-shaped. 
Life satisfaction falls in our 20s and 30s, then hitting a low in our late 40s before increasing until our 80s.

The happiness curve

According to a study by economists, the U-curve is generally noticed at age 46. It tends to appear in wealthier countries.
However, some economists and psychologists factor in the possibility that those who become happier in the studies are the same people who are content in their early years.

When the U-curve occurs

When Jonathan Rauch fell into the doldrums in his 40s, he had no idea why. Life was good: he had a successful career, a solid relationship, good health and sound finances. Then he learnt about the happiness curve and it all became clear.

The midlife slump

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