One measure of the decline of church strength and authority is church membership and attendance. And by that measure, US secularity is rising to surprising heights.
Churches try to keep track of their members, and if their numbers get a little inflated, you could understand why. People who hardly ever attend services, or who get listed just because the whole family has been listed for many years, can get included in church membership rolls. Still, there's no need to suppose that serious membership inflation is that rampant. In recent decades, many denominations have seen slow declines in attendance and membership, declines impossible to hide. Fairly honest reporting of that data is necessary to prevent denominational leaders from fooling themselves. Churches don't regard people showing up just a few times a year as real church-goers, and they search for ways to convert them into regular members. Just keeping people in the pews is a full-time job in itself for plenty of congregations.
The March 2012 Gallup poll on religious behavior in the United States exposes how lots of people are avoiding church. As Gallup reports, "32 percent of Americans are nonreligious, based on their statement that religion is not an important part of their daily life and that they seldom or never attend religious services."
About a third of Americans now report that they seldom or never go to a religious house of worship. That's a huge number of people avoiding church-going. But keep in mind, this poll does say that 68 percent of Americans claim that they do occasionally attend services. How valid is that figure? Actually, even fewer people are real church-goers.
America's congregations could only wish that 68 percent of Americans were showing up once in a while. It's terribly nice that polls can still find upwards of 85 percent claiming to be Catholic, Protestant, Jewish, and so on, but those expressions of religious identity are evidently detached from behavior. You couldn't blame churches for feeling annoyed at the way that religious people constantly exaggerate how often they attend services. Poll after poll "discover" that plenty of people go to church frequently, but it is obvious how people lie about going to church. According to studies of people's actual behavior, less than 25 percent of Americans go to church two-three times or more each month. These low numbers have been known for a while, but little noticed. University of Michigan researcher Philip Brenner has studied church attendance for many years (see his 2011 paper and discussion by Tom Rees at Epiphenom , and plenty of further data is reported by Rebecca Barnes and Lindy Lowry at churchleaders.com.
The churches' own membership lists reflect how at least three-quarters of Americans aren't showing up to church much at all. The Association of Statisticians of American Religious Bodies has periodically collected data from America's churches about their membership, and the latest report is available: 2010 U.S. Religious Census: Religious Congregations & Membership Study. As it reports, the population of the United States was 308,745,538 in 2010. How many Americans are church members? Just 150,686,156 Americans. That sounds like a lot of people, and it is, but that is only 48.8 percent of the total population. That means 51.2 percent of Americans don't have church membership nowadays, and that's a surprising measure indicating rising secularity.
A bare majority of Americans are not connected with any religious congregation, and an even larger majority are hardly ever showing up in any house of worship. There's plenty of other sorts of religious activities and spiritual experiences to pursue, of course. Abandoning church is not the same thing as leaving the religious life. All the same, church-goers have become a minority in America.