You may recall Facebook's Gross National Happiness project, it which it tried to measure happiness around the U.S. based on positive and negative words used with status updates. Now the company has taken the project on a more global scale.

They didn't measure every country. They just measured the ones with the highest volumes of status updates in one of the languages they support: English, Dutch, German, Italian and Spanish.

"We found that a country's happiness score is representative of the country's culture and experience on a particular day," says Facebook's Lisa Zhang. "Besides popular holidays like Christmas and New Year's Day, we see a spike in Spain's happiness index corresponding to Saint Jordi's day in Apri. In India, Holi in March and its Independence Day in August also lead to peaks, as do big sports victories in many of the countries. In the United States, we see similar spikes every Super Bowl."

"Sports also can lead to some of the lowest days in the happiness index," she adds. "Ireland's score drops on Nov 18, 2009, when FIFA awarded a controversial win to France over Ireland in the World Cup playoffs. Similarly, Germany's happiness level dips on Nov 10, 2009, when the goalie Robert Enke committed suicide."
Zhang also notes that disasters had a dramatic effect on happiness levels.

Facebook claims that nobody within the company reads status updates to conduct the analysis. The graph can be seen country-by-country here.