(VOV) - Vietnam is considered the second happiest country in the world, behind Costa Rica, with Colombia third, despite the residents constant groaning over traffic jams and overcrowded hospitals and schools. The ranking were compiled by the Happy Planet Index, and published by the New Economics Foundation, an independent UK think tank. The Happy Planet Index ranks countries based on the health and happiness they produce per unit of environmental input, using global data on life expectancy levels, happiness and environmental sustainability. This year’s rankings see a rise in Vietnam position when compared to previous years.