When we, as individuals, examine our own lives, we tend to view them in distinct parts, symbolically divided by milestones like graduations, marriage, new jobs, etc. Perhaps the easiest and most popular way to talk about the stages of our lives is to go by decade. They distinctly package and represent the stages of our lives.
Psychologists Adam Alter and Hal Hershfield argue that at the end of a decade, when one’s age end in a “9” (for example: 29, 39 or 49) – one is much more likely to reflect on the meaning and future of one’s life. One tends, at this important moment, to take stock and critique, often setting new goals or changing directions if one is dissatisfied with the current picture.
Alter and Hershfield analyzed data from the World Values Survey and found that, out of answers from 42,000 individuals spread across the globe, people at an age ending in 9 were much more likely to be examining their lives. Further study showed that this time-related reflection often causes “maladaptive behaviors”, actions which were abnormal or detrimental. For example, the team studied data from a website catering to people seeking extra-marital affairs. It turned out that among eight million male members of the site, “nine-ers” were over-represented by 17.988 percent. The same was found when looking at female user age distribution.
Alter and Hershfield’s research also shows that nine-ending age reflection proves to be too much for many people. Examining suicide statistics collected by the US Center for Disease Control and Prevention from the years 2010-2011 showed that “nine-ers” commit suicide more often than individuals of any other age.
On a more positive note, the unique moment of entering a new decade of life, which happens only a handful of times in one’s life, can also have positive results, like the setting of new goals for one’s self. Data from the Athlinks.com website revealed that “nine-ers” were over-represented by 48 percent among 500 first-time marathon runners. In addition, “nine-ers” also performed better: runners achieved better times, by an average of 2.3 per cent, when they were aged 29 or 39, as opposed to when they were a couple of years younger.
Alter and Hershfield explain, “We find that people are significantly more likely to consider whether their lives are meaningful as they approach the start of a new decade.”