The American Religious Identification Survey (ARIS) is a telephone survey conducted to find out the religious preferences and opinions of the American public. The first such survey was conducted in 1990 on a base group of 113,000 interviews. The most recent study, released on March 9, 2009, indicates that almost all religious groups have lost overall ground as a measure of percentage points, while those claiming "no religion" have almost doubled.USA Today: Most religious groups in USA have lost ground... (March 9, 2009)

The United States census has never asked questions regarding religious preferences during it's survey of the population once every ten years. Several other organizations do, however, poll the American public from time to time in regards to religious matters. One such group has conducted three studies over a period of 18 years with over 200,000 participants. Funded by private organizations, the group has collected a large amount of religious demographic data since the first survey in 1990. The latest results of the ARIS survey show a large shift predominately from the Catholic faith into the no-faith group. The group indicating that they had "no religion" was the only group to increase their numbers in every state of the union.USA Today: Most religious groups in USA have lost ground... (March 9, 2009) Some pundits have claimed that Atheist groups are happy about the news, while Christian groups are pointing out that 76 percent of all Americans still consider themselves to be Christian.ChristWire: American Religious Identification Survey 2008 Released... (March 9, 2009)