Global data are based on the Gallup World Poll conducted in more than 100 countries and areas each year since 2006. The surveys of roughly 1,000 adults per country are nationally representative of those aged 15 and older in each country, conducted either by phone or in person.
U.S. data are based on nationally representative telephone surveys of adults aged 18 and older. Data from individual polls are generally based on surveys of 1,000 national adults, while annual data may represent combined data from quarterly or monthly surveys. Results are weighted to ensure the sample demographics conform with the most recent U.S. Census targets.