If you're planning to take a vacation soon, this news might convince you to go to Denmark. The annual World Happiness Report just found it to be the happiest country on Earth.The findings come ahead of the U.N.'s World Happiness Day on March 20, and just months after a separate U.S. News & World Report survey found that Denmark is the happiest country for women.Other top contenders on the list of happiest countries include Switzerland, Iceland, Norway, Finland, Canada, the Netherlands, New Zealand, Australia, and Sweden. The United States landed in 13th place. The Sustainable Development Solutions Network, which ranked 156 countries for the report, launched the results during a well-being conference at the Bank of Italy.Jeffrey Sachs, director of the Earth Institute at Columbia University and an editor of the report, said in a statement that countries should focus on achieving well-being as they pursue development goals. "Rather than taking a narrow approach focused solely on economic growth, we should promote societies that are prosperous, just, and environmentally sustainable," Sachs said in the statement.To create the final list, researchers used self-reported data based on people evaluating their happiness levels on a scale from 0 to 10. "Key variables" in the rankings included "real GDP per capita, healthy life expectancy, having someone to count on, perceived freedom to make life choices, freedom from corruption, and generosity," according to a press release.Read the full World Happiness Report here