Since it was first published in 2012， the World Happiness Report demonstrated that well-being and （A） h are critical indicators of a nation's economic and social development， and should be a key aim of policy. This year's report looks at the changes in happiness levels in 158 （B） c ， and examines the reasons behind the statistics. The World Happiness Report 2015 will give world leaders the opportunity to reshape the global agenda and move the world towards a sustainable development agenda that includes well-being as an essential （1） e .

"The aspiration of society is the flourishing of its members，" said Jeffrey Sachs， Director of the Earth Institute， Columbia University. "This report gives （C） e on how to achieve societal well-being. It's not by money alone， but also by fairness， honesty， trust， and good （D） h . The evidence here will be useful to all countries as they pursue the new Sustainable Development Goals."

The World Happiness Report 2015 identifies the countries with the highest levels of happiness： 1. Switzerland， 2. Iceland， 3. Denmark， 4. Norway， 5. Canada.

The （2） r reveals trends in the data judging just how happy countries really are. On a scale running from 0 to 10， people in over 150 countries， surveyed by Gallup over the period 2012–2015， reveal an average （3） s of 5.1 （out of 10）. Six key variables explain three-quarters of the variation in annual national average scores over time and among countries： real GDP per capita， healthy life expectancy， having someone to count on， perceived freedom to make life choices， （E） f from corruption， and generosity.

A positive outlook during the early stages of life is inherently desirable， but it also lays the （4）

f for greater happiness during adulthood， Scientists hold that society must invest early on in the lives of the （F） c so that they grow to become independent， productive and happy adults， contributing both socially and economically.

（A， B， C， D， E， F FOR CROSS， 1， 2， 3， 4 FOR DOWN. The first letters of the absents were given）

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