As Roman Catholics cardinals conclave to pick a new Pope, they should be thinking about a problem that is becoming more apparent - in the developed world, all organized religion continues to decline.

Religious affiliation in the US only began to be tracked in the 1930s but newly released survey data shows the curve continuing to go down. Last year, 20 percent of Americans claimed they had no religious preference, more than double the number reported in 1990. It doesn't mean they are atheists, that is 3% of the public, but that they do not subscribe to an organized religion. 'Spiritual' is the catch-all phrase they tend to use.

Results of General Social Survey, a highly cited biannual poll conducted by the NORC of the University of Chicago, are being released now and over the coming weeks. On American attitudes toward religion, survey results showed that 20 percent of a nationally representative group reported no religious preference. That's a jump from 1990 when 8 percent of Americans polled identified with an organized faith.

Responses in the survey were to the question, "What is your religious preference? Is it Protestant, Catholic, Jewish, some other religion, or no religion?"

An analysis of the results by sociologists from UC Berkeley and Duke University suggests the following:

  • Liberals are far more likely to claim "no religion" (40 percent) than conservatives (9 percent)
  • Men are more likely than women to claim "no religion" (24 percent of men versus 16 percent of women).
  • More whites claimed "no religion" (21 percent) compared to African Americans (17 percent) and Mexican Americans (14 percent).
  • More than one-third of 18-to-24-year-olds claimed "no religion" compared to just 7 percent of those 75 and older.
  • Residents of the Midwestern and Southern states were least likely to claim "no religion" compared to respondents in the Western, Mountain and Northeastern states. But Midwesterners and Southerners are catching up, Hout said.
  • Educational differences among those claiming "no religion" are small compared to other demographic differences.
  • About one-third of Americans identify with a conservative Protestant denomination, one-quarter are Catholics (although 35 percent were raised Catholic) and 1.5 percent are Jewish.