What would make you happy? Wealth? Fame? Power?
Perhaps. But according to one of Australia's leading demographers the key to happiness is something far less sexy.
KPMG demographer Bernard Salt says having the self-discipline to control the excesses of modern life is the secret to happiness in the 21st century.
"What makes people happy later in life is the ability to make the right choices: in cultivating strong relationships, in having the ability to manage debt, to build strong friendships, to maintain a balanced approach to exercise and weight control,'' Mr Salt says.
"Manage these things and you are set for a happy life.''
Mr Salt based his findings on a recent KPMG survey of more than 2000 Australians.
The survey found those who were the most unhappy felt they were overweight, burdened with debt and didn't have enough friends.
External factors such as job security and not being paid enough did not feature prominently, he said.
"You are in control of your own happiness, you are in control of your own destiny, it comes as a result of the decisions you make.''
However, it seems money does buy happiness, at least to an extent.
According to the survey those households earning more than $A250,000 ($NZ311,261) a year were among the happiest - although this could be due to people in that range having lower proportional debts, Mr Salt said.
The least happy group of respondents were people aged 45-49, who were more likely to have several credit cards, be unhappy in their relationships and the least likely to have holidays or eat out.
"At that time in life, the stresses are maximised, you've got kids, you've got teenagers, you've got maximum debt you are trying to pay back, you're trying to get ahead in your job - it all comes together in your late 40s.''
However, for those struggling through their 40s, there are better times ahead - those in their 60s were among the happiest respondents and among those most likely to take holidays.
Do you believe eating superfoods makes you healthier?Related story: (See story)