"Atheists are heavily concentrated in economically developed countries, particularly the social democracies of Europe. In underdeveloped countries, there are virtually no atheists. Atheism is a peculiarly modern phenomenon. Why do modern conditions produce atheism? In a new study to be published in August, I provide compelling evidence that atheism increases along with the quality of life (1).
The reasons that churches lose ground in developed countries can be summarized in market terms. First, with better science, and with government safety nets, and smaller families, there is less fear and uncertainty in people's daily lives and hence less of a market for religion. At the same time many alternative products are being offered, such as psychotropic medicines and electronic entertainment that have fewer strings attached and that do not require slavish conformity to unscientific beliefs."
Psychologytoday.com, Nigel Barber, Ph.D, July 14, 2011