According to this research looking at changes in belief in God internationally since 1991, theism is gradually declining, but is increasing in a few places such as Russia, Slovenia and Israel. (The last one is a bit of a surprise. Maybe the Holocaust took its toll in that respect.)
But in an international survey that did not include China, one surely couldn't place too much faith in the accuracy of the estimates.
The most curious part of the research is perhaps this:
Belief is highest among older adults. On average, 43 percent of those aged 68 and older are certain that God exists, compared with 23 percent of those 27 and younger, according to the report.
"Looking at differences among age groups, the largest increases in belief in God most often occur among those 58 years of age and older. This suggests that belief in God is especially likely to increase among the oldest groups, perhaps in response to the increasing anticipation of mortality," Smith said.
He noted that the higher level of belief was not simply a cohort effect, in which people carry forward attitudes shaped in younger years.
In the United States, for instance, 54 percent of people younger than 28 said they were certain of God's existence, compared with 66 percent of the people 68 and older.
In countries with low overall belief in God, the difference in belief between age groups is also strong. In France, for example, 8 percent of younger people said they were certain that God exists, compared with 26 percent of the people 68 and older. In Austria, 8 percent of the younger generation said they were certain in their belief, while 32 percent of people 68 and older were confident of God's existence.
I'm not sure if this is somehow related to decreasing belief in global warming amongst older people, which has often shown up in surveys. (I have long been maintaining that such denial is, essentially, a matter of faith in its own way.) It's worth remembering, though, in the US at least, all ages in the Evangelical churches are prominent disbelievers in AGW. On the other hand, I'm pretty sure Catholics in any country are more likely to not dispute it.
Someone else will have to work out what this all means.