Research by neuroscientists Richard Davidson and V.S. Ramachandran and by psychologist Shawn Achor proves that happiness improves work performance.

According to the American Psychological Association:

“Job stress costs U.S. businesses an estimated $300 billion per year through absenteeism, diminished productivity, employee turnover and direct medical, legal and insurance fees.”

SOME OF THE CAUSES OF WORKPLACE STRESS ARE:

Low salaries, excessive workload, few opportunities for advancement, work that isn’t engaging, lack of social support, not enough control over job-related decisions, conflicting demands or unclear performance expectations

Shawn Achor explains:

“25% of job successes are predicted by IQ, 75 percent of job successes are predicted by your optimism levels and your social support.”

“If you can raise somebody’s level of positivity in the present, their brain experiences what we now call a happiness advantage, which is your brain at positive performs significantly better than at negative, neutral or stressed.”

WHAT DOES HAPPINESS ADVANTAGE MEAN?
1-
Your intelligence, creativity and your energy levels rise.
2- Your brain at positive is 31% more productive than your brain at negative, neutral or stressed. You’re 37% better at sales. Doctors are 19 % faster and more accurate at coming up with the correct diagnosis.
3- Dopamine, which floods into your system when you’re positive, makes you happier and it turns on all of the learning centers in your brain.

We can reverse the formula for happiness and success, and in doing so, not only create ripples of positivity, but a real revolution.”

Source:
http://www.apa.org/helpcenter/labor-day.aspx
https://www.apaexcellence.org/resources/creatingahealthyworkplace
https://www.ted.com/talks/shawn_achor_the_happy_secret_to_better_work
https://www.cdc.gov/niosh/docs/99-101