Thailand is the 32nd happiest country in the world while Norway ranked first, according to a report released at the United Nations to mark the International Day of Happiness on Monday.
The World Happiness Report 2017, which surveyed 155 countries, was conducted by the Sustainable Development Solutions Network (SDSN), a global initiative launched by the UN in 2012. With the release, the SDSN called on nations to build social trust and equality to improve the well-being of their citizens.
Thailand also ranked 19th of the top 20 gainers, which showed average ladder scores increasing by 0.50 or more from the previous ranking done in 2005-07, while Nicaragua made the biggest leap.
In Asia-Pacific, the kingdom trailed only New Zealand (6), Australia (9) and Singapore (26).
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Elsewhere in Asean, Malaysia ranked 42nd, followed by Indonesia (81), Vietnam (94), Myanmar (114) and Cambodia (129). Laos and Brunei were not included in the survey.
The ranking took into consideration six variables: economic factors in the form of gross domestic product per capita, social support such as education and family life, healthy life expectancy, freedom to make life choices, generosity and perceptions of corruption.
In the case of Thailand, social support made up the largest part of the total score, followed by GDP per capita. According to Trading Economics data, Thailand's GDP per capita was $5,775.10 in 2015 and averaged $2,532.32 between 1960 and 2015.
Worldwide, Norway displaced Denmark as the world's happiest country.
The Nordic nations are the most content while countries in sub-Saharan Africa, along with Syria and Yemen, are the least happy of the countries ranked in the fifth annual report.
"Happy countries are the ones that have a healthy balance of prosperity, as conventionally measured, and social capital, meaning a high degree of trust in a society, low inequality and confidence in government," Jeffrey Sachs, the director of the SDSN and a special adviser to the UN secretary-general, said in an interview.
The aim of the report, he added, is to provide another tool for governments, business and civil society to help their countries find a better way to well-being.
Denmark, Iceland, Switzerland, Finland, Netherlands, Canada, New Zealand, Australia and Sweden rounded out the top 10 countries.
South Sudan, Liberia, Guinea, Togo, Rwanda, Tanzania, Burundi and the Central African Republic were at the bottom.
Germany was ranked 16, followed by the United Kingdom (19) and France (31). The United States dropped one spot to 14.
Mr Sachs said the US is falling in the ranking due to inequality, distrust and corruption. Economic measures that the administration of President Donald Trump is trying to pursue, he added, will make things worse.
"They are all aimed at increasing inequality -- tax cuts at the top, throwing people off the healthcare rolls, cutting Meals on Wheels in order to raise military spending. I think everything that has been proposed goes in the wrong direction," he explained.
"The lowest countries are typically marked by low values in all six variables," said the report, produced with the support of the Ernesto Illy Foundation.
Mr Sachs would like nations to follow the United Arab Emirates and other countries that have appointed Ministers of Happiness.
"I want governments to measure this, discuss it, analyse it and understand when they have been off in the wrong direction," he said.