The news today is a new poll from Pew Research identifying a significant decline in the number of Americans who call themselves "Christian". Strikingly, the rate of decline is just as high for the catholics as for the Mainline. The Evangelicals are more or less holding their own, but the "unaffiliated" which includes atheists, agnostics, spiritual-but-not-religious, and whatevers, is now nearly 23%. The younger and better educated you are, the more likely you are a "none".
The New York Times comments,
The decline has been propelled in part by generational change, as relatively non-Christian millennials reach adulthood and gradually replace the oldest and most Christian adults. But it is also because many former Christians, of all ages, have joined the rapidly growing ranks of the religiously unaffiliated or “nones”: a broad category including atheists, agnostics and those who adhere to “nothing in particular.”What explains this? One possibility:
The report does not offer an explanation for the decline of the Christian population, but the low levels of Christian affiliation among the young, well educated and affluent are consistent with prevailing theories for the rise of the unaffiliated, like the politicization of religion by American conservatives, a broader disengagement from all traditional institutions and labels, the combination of delayed and interreligious marriage, and economic development.The article continues,
Nearly a quarter of people who were raised as Christian have left the group, and ex-Christians now represent 19 percent of adults.There's a wealth of information here and you can break it out by denomination. For example, check out the demographics of the Episcopal/Anglican group here.
Attrition was most substantial among mainline Protestants and Roman Catholics, who have declined in absolute numbers and as a share of the population since 2007. The acute decline in the Catholic population, which fell by roughly 3 million, is potentially a new development. Most surveys have found that the Catholic share of the population has been fairly stable over the last few decades, in no small part because it has been reinforced by migration from Latin America.