Human Journey

The Eighth Habit of Highly Effective People? Avoiding Summer Birthdays

Photo by James P. Blair

Want your kids to be a high-flying corporate execs? If so, you may want to avoid giving birth to them during the summer months. A new study from the Sauder School of Business at the University of British Columbia finds that babies born in June or July are less likely to become CEOs at S&P 500 companies than those with spring birthdays. Only 5.87% of S&P CEOs were born in July as compared to 12.53% born in March.

According to study co-author Maurice Levy, “Summer babies underperform in the ranks of CEOs as a result of the ‘birth-date effect,’ a phenomenon resulting from the way children are grouped by age in school.” In the U.S., kids born in June and July tend to be the youngest students in their classes, while those born in March and April are the oldest. This factors in kids who were held back or accelerated because they were born in months close to the cut off dates.

“Older children within the same grade tend to do better than the youngest, who are less intellectually developed,” notes Levi. “Early success is often rewarded with leadership roles and enriched learning opportunities, leading to future advantages that are magnified throughout life.”

If plotting out your babies’ birth dates in advance seems a bit over-the-top, there is another potential solution to the “birth-date effect”: enrolling kids in school only when they are ready.

For all the latest science news, check out National Geographic Library’s twice-weekly news rundown, EarthCurrent.

Since 2005, Michael has been a librarian at National Geographic.
  • Ima Ryma

    August 30th, I was born.
    Some study would say my birthday
    Should get me depressed and forlorn,
    Cuz in grade school, kids born in May,
    Older than me got dibs on smarts,
    And the teacher picked them more to
    Perform the class leadership parts,
    Leaving us younger zilch to do.
    And all grown up, the May folks would
    Be CEOs of biggest incs.,
    While we the younger only could
    Live how an August birthday stinks.

    I did beat the odds – doncha know!
    I’m Warren Buffett – C.E.O.

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