The Gallup poll has the broadest definition of irreligion: the question "Is religion an important part of your daily life?" was asked; the "no" answer is represented below. Dentsu Communication Institute provides data for respondents who stated they have "no religion". Phil Zuckerman uses only the number who describe themselves as atheist or agnostic. The numbers come from different years, and might not be accurate for countries with governments that require or urge religion or secularism.
Countries with the greatest number of people without religion (including agnostics and atheists) based on the total population of each country as of 2004 and the percentage of nonreligious people according to Zuckerman:7