University of Warwick researchers have found evidence supporting the theory that links happiness and productivity. Economists from the institution discovered that happiness gives people the drive to work harder and increases their productivity by 12 percent.

For the study, the researchers conducted several experiments on more than 700 participants. Respondents were either shown a comedy movie clip; given free chocolate, drinks and fruit or questioned about recent family tragedies like bereavements to determine whether lower levels of happiness could directly be linked to lower levels of productivity.

"Companies like Google have invested more in employee support and employee satisfaction has risen as a result. For Google, it rose by 37%, they know what they are talking about. Under scientifically controlled conditions, making workers happier really pays off," Professor Andrew Oswald said in a press release.

Google is best known for providing perks to its employees like laundry facilities, nap pods, free food, transport, gym facility, sports courts and even slides to commute between floors.

Dr Daniel Sgroi from the Department of Economics said that happier workers seemed to use time more effectively. Their speed also increased without compromising on quality.

"This research will provide some guidance for management in all kinds of organizations, they should strive to make their workplaces emotionally healthy for their workforce," Dr Eugenio Proto said.

The finding is published in the Journal of Labor Economics.

A 2013 Gallup study found that only 30 percent of American employees felt occupied or enthused by their jobs, while the other 70 percent were not utilizing their full potential. The 2013 State of the American Workplace Report estimated that extensive disinterest and discontent in professional life not only impacted a company's performance but also cost the U.S. $450 billion to $550 billion per year, CBS News reports.

A 2011 University of Illinois study found that happy people were more likely to live longer and experience better health than their unhappy peers. The finding was based on a review of more than 160 studies of human and animal subjects. The study was published in the journal Applied Psychology.

"We reviewed eight different types of studies," professor emeritus of psychology Ed Diener said in a statement. "And the general conclusion from each type of study is that your subjective well-being - that is, feeling positive about your life, not stressed out, not depressed - contributes to both longevity and better health among healthy populations."