* The survey is conducted online, every month in 25 countries. Participating countries include: Argentina, Australia, Belgium, Brazil, Canada, China, France, Germany, Great Britain, India, Indonesia, Italy, Japan, Mexico, Norway, Poland, Russia, Saudi Arabia, South Africa, South Korea, Spain, Sweden, Turkey, and the United States of America.
* An international sample of over 18,000 adults aged 18-64 in the US and Canada, and age 16-64 in all other countries, are interviewed monthly. Approximately 1000 individuals participate in each country with the exception of Argentina, Belgium, Hungary, Indonesia, Mexico, Poland, Russia, Saudi Arabia, South Africa, South Korea, Sweden and Turkey, where each have a sample 500.
* Results are weighted to balance demographics and ensure that the sample's composition reflects the adult population of each country according Census data.
* A survey with an unweighted probability sample of this size and a 100% response rate would have an estimated margin of error of +/-3.1 percentage points (sample of 1,000), or +/- 4.5 percentage points (sample of 500), 19 times out of 20, had the entire population of adults in each country been polled.
Results are nationally representative. Respondents are general population, aged 16 – 64 years of age with the exception of China, India, and South Africa where the sample is made up of more affluent adults.