When You're Smiling, The Greenbacks Multiply -- Smiile, Kid, You'll Get Richer!

Earning more money tends to make people happier, and happier people actually go on and make more money.

In a study of more than 10,000 Americans, those who experienced more positive daily emotions and felt more satisfied with their lives while growing up earned more income by age 29.

Published by the National Academy of Sciences of the USA, it was on the agenda of the American Economic Association's annual meeting on Friday.

The analysis suggests happiness isn't just linked to higher income-- it is helping to generate it. Contrarily, being unhappy hurts more. Those who experienced "profoundly unhappy" adolescence made about 30% less than the average income, the paper found.