Dr. Jan-Emmanuel De Neve of the University College London and Andrew Oswald of the University of Warwick analyzed data from 15,000 U.S. adolescents and young adults and found those who reported higher "positive affect" -- a technical measure of happiness, or higher "life satisfaction" -- grow up to earn significantly higher levels of income later in life.
The study found happy individuals' greater wealth was due, in part, to the fact that happy people were more likely to get a degree, find work and get promoted more quickly than their gloomier counterparts.
Greater happiness had a big financial impact: for example, a one-point increase in life satisfaction -- on a scale of of 1 to 5 -- at the age of 22 was associated with almost $2,000 higher earnings per annum at the age of 29.
De Neve and colleagues said even with children growing up in the same family, happier siblings tended to go on to earn higher levels of income.
"Perhaps most importantly, for the general public -- and parents in particular -- these findings show that the emotional well-being of children and adolescents is key to their future success, yet another reason to ensure we create emotionally healthy home environments," De Neve said in a statement.