The buckle of the Bible belt has been located—in Shreveport, La. It is the most Christian city in the nation, according to a study by the Barna Group.

The Christian research organization found 98% of Shreveport residents describing themselves as Christian, ahead of Birmingham, Ala., and Charlotte, S.C. (both 96%), Nashville (95%) and Greenville, S.C. and Asheville, N.C. (94%).

The results were revealed in two new Barna studies, Markets 2011 and States 2011, based on nearly 40,000 interviews conducted in the last seven years. The lowest shares of self-identified Christians were found in San Francisco (68%), Portland, Ore. (71%), Portland, Maine (72%), and Seattle, Sacramento, Calif., and New York City (each 73%).

Leading areas tending toward skepticism about religion were Seattle and Portland, Maine, where 19% of the population identified themselves as being atheist or agnostic. The markets with the largest share of unchurched adults included San Francisco, 44% of whom had not been to a religious worship service in the last six months, and Portland, Maine (43%).

Weekly church attendance was found to be highest among the residents of Birmingham (67%), followed by Baton Rouge, La. (62%), Salt Lake City (62%) and Huntsville, Ala. (60%). Areas with the highest proportions of Christians attend megachurches—1,000 or more adults—included Las Vegas, Dallas, San Diego, Orlando, Fla., Tampa-St. Petersburg, Fla., and Houston.

Church volunteers were most frequently reported in Charlotte and Salt Lake City, while the markets with the highest proportion of volunteers for nonprofits, other than churches, were Tucson and Seattle.

David Kinnaman, who directed the research project, said that the study "confirmed many spiritual assumptions about various regions of the country. The South hosts many of the nation's Christians, while the West and Northeast play to more secular stereotypes."

However, "one of the underlying stories is the remarkably resilient and mainstream nature of Christianity in America. Nearly three out of four people call themselves Christians, even among the least ‘Christianized' cities," he added.

"Furthermore, a majority of U.S. residents, regardless of location, engage in a church at some level in a typical six-month period. The real differences spiritually between various regions are not so much what they call themselves; the faith gaps are more likely to be issues of belief, practice, politics and spiritual emphasis--how people think about, prioritize and express their faith."

Source: The Barna Group.

To read the report in full, go to http://www.barna.org/faith-spirituality/435-diversity-of-faith-in-various-us-cities.