Atheism Has Lowest Retention Rate of Any Religion

Msgr Charles Pope on the Archdiocese of Washington blog has a post up linking to a post on 1964, the Center for Applied Research in the Apostolate blog out of Georgetown university, which looks at the retention rate of various religions and denominations: the percentage of people born into that belief system who continue to profess that same belief system as adults. The data that CARA is looking at comes from a Pew Forum survey in 2008 called the U.S. Religious Landscape Survey. What this survey shows is that Hindus have the highest retention rate of any faith in the US with 84% of people raised Hindu still identifying as Hindu.  Greek Orthodox have the highest retention rate of any Christian church at 73% and Catholics rank higher than any Protestant denomination at 68%.  (Other data that I've seen, which fits well with this, has shown that people born Catholic are 1/3 practicing Catholics, 1/3 identifying as Catholic but no longer practicing and 1/3 no longer identifying as Catholic.  Most people undergo these changes between their teenage years and their 30s.)  The lowest ranking religious identifications in terms of retention are "nothing in particular" at 38% retention, Jehovah's Witnesses at 37%, Congregationalists at 37% and at the very bottom atheists at 30%.

It should be noted that the atheist sample is fairly small, and that the majority of people who identify as atheists as adults were not raised as atheists. CARA goes into detail as follows:

Some of the retention rates in the figure above were never provided in Pew's original report. These are calculated from the original data sets released by Pew for this study (one for the continental U.S. and another for Alaska and Hawaii). In these data there are 432 weighted respondents who say they were raised as Atheists. A total of 131 of these individuals self-identify as an Atheist at the time of the survey resulting in an estimated retention rate of 30%. However, there were a total of 1,387 Atheists (weighted) identified in the survey (equivalent to 1.6% of the adult population). What these findings reflect is that in the U.S. Atheists are for the most part "made" as adults after being raised in another faith. It appears to be much more challenging to raise one's child as an Atheist and have them maintain this identity in their life. Of those raised as Atheists, 30% are now affiliated with a Protestant denomination, 10% are Catholic, 2% are Jewish, 1% are Mormon, and 1% are Pagan.