Religion's on its way out in every one of nine countries studied by a team of scientists.
Daniel Abrams and Haley Yaple of Northwestern University, together with Richard Wiener of the Research Corporation for Science Advancement, used dynamical systems and perturbation theory to analyze the growth and decline of religious groups.
They examined census data for the last 100 years from Australia, Austria, Canada, the Czech Republic, Finland, Ireland, the Netherlands, New Zealand and Switzerland.
They found that about half of all people in the Netherlands, for instance, identify themselves as having no religious affiliation, and that in the Czech Republic unaffiliated people are in the majority - accounting for 60 percent of the population.
And it's all going one way only, they say. Generally speaking, the more members a social group has, the more attractive it's seen as being. Conversely, once membership begins to slip, it's a decline that's hard to reverse.
The team's model examined the perceived advantages and disadvantages of belonging to religious and non-religious groups.
"Our model predicts that in many modern secular societies, religions will continue to lose members and be driven toward extinction," says Wiener.
Similar methods have been used in the past to examine other social phenomena. Abrams and Steven Strogatz used the same type of nonlinear dynamicsto predict that about 80 to 90 percent of the languages in use today are doomed to die by the end of the century.