I recently read an essay about the decline in religious belief, but prior to this, I was convinced of it through personal observation, and interaction with many people who have abandoned their faith. Titled Why The Gods Are Not Winning, it was written by Gregory Paul & Phil Zuckerman, and published in 2007.
Here are some extracts:
Religion is in serious trouble. The status of faith is especially dire in the west, where the churches face an unprecedented crisis that threatens the existence of organized faith as a viable entity, and there is surprisingly little that can be done to change the circumstances.
God belief is not dead in these nonreligious democracies, but it is on life support. The ardent hopes of C. S. Lewis and John Paul II to reChristianize Europe have abjectly failed.
In the end what humanity chooses to believe will be more a matter of economics than of debate, deliberately considered choice, or reproduction. The more national societies that provide financial and physical security to the population, the fewer that will be religiously devout. The more that cannot provide their citizens with these high standards the more that will hope that supernatural forces will alleviate their anxieties. It is probable that there is little that can be done by either side to alter this fundamental pattern.
Grab the rest here.