Despite complaints of traffic jams and overcrowded hospitals and schools, Viet Nam is considered the second happiest country in the world in terms of sustainable well-being — behind Costa Rica.

The ranking, called the Happy Planet Index, was compiled and released by the New Economics Foundation, a UK independent think tank that wanted to create an index that measured the sustainability of a country and the happiness of its people (summing up how efficient is their happiness).

The report, published June 14, ranks the UK ahead of all other G8 and EU nations, 41st out of 151 countries globally, calculated by using global data on life expectancy, experienced well-being and ecological footprint.

Costa Ricans have higher average life expectancy and well-being than people living in the United States and the country has a per capita Ecological Footprint one third the size of that of the US. Of the nine countries closest to achieving happy, green lives, eight are in Latin America and the Caribbean. Colombia came in third behind Vietnam.

The Happy Planet Index was first published in 2006. The 2012 report is the third issued. Learn more at www.happyplanetindex.org.

You can calculate your own personal happy planet score using a survey on their website: survey.happyplanetindex.org.