The worrying discovery, which was recently published in the Australian Journal of Education, indicates it might be important to decide on a career earlier than previously thought, as those without a clear plan were found to earn far less over the course of their working lives.

The Longitudinal Study of Australian Youth (LSAY) was led by Australian National University sociology lecturer Joanna Sikora, who questioned a group of 16-year-olds about their career plans in 2006, and then checked in with them again a decade later to see how their careers were progressing once they had turned 26.

Dr Sikora then worked out their expected lifetime earnings based on the jobs they had at 26, and found those who didn’t know exactly what they wanted to do could experience a six per cent earnings disadvantage during their lifetime.

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She told Fairfax media respondents who didn’t have “occupational expectations” in their teenage years — including those who had only vague career plans, such as working with animals or earning a fat salary — were more likely to still be unsure seven years later.

At that point, career uncertainty started to affect future earnings — and it also tended to stop the respondents from pursuing degrees and training which were more likely to lead to higher earning potential.

“There are arguments that this lack of direction is beneficial, because it keeps young people open to different opportunities,” Dr Sikora told the Sydney Morning Herald.

“But it doesn’t work like that, particularly for the young people who could and might have gone into a path way that leads to professional occupations.

“Young people who are uncertain do a little bit worse in terms of how much education they get by the time they are 26, and what kind of jobs they entered by then.”

According to Dr Sikora, students from disadvantaged backgrounds reported higher levels of uncertainty, and while uncertain teens may end up catching up with their cohort later in life, that outcome was unlikely.

The findings contradict common reassurances given to teens by well-meaning parents and teachers, who tend to insist big career decisions can still be made later in life with no consequence.

It’s also concerning because, as the study discovered, “a considerable proportion of adolescents have no clear occupational plans”, with 22 per cent of adolescent boys and 17 per cent of teen girls having little clue about their future careers.

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