A study of American religious identification shows that themajority of adult adherents continue to be tied to Protestant and othernon-Catholic denominations but the numbers of those who say they arenon-Christians or have no religion have risen substantially.

The American Religious Identification Survey, 2001, releasedMonday by the Graduate Center of the City University of NewYork, is a follow-up to a survey conducted in 1990. It found that 52 percent of American adults are Protestant,24.5 percent are Catholic and 14.1 percent are not affiliated with areligion. Researchers determined that 1.3 percent of adult Americansdescribed their religion as Jewish and 0.5 percent as Muslim.

The results, based on more than 50,000 adult respondents, found thatProtestant and other non-Catholic denominations continue to have themajority of adult adherents--more than 105.4 million--but theirproportion dropped from 60 percent in 1990 to 52 percent in 2001.

The number of adults who identify with a non-Christian religion rosedramatically from about 5.8 million to 7.7 million. Their proportionincreased slightly--to 3.7 percent from 3.3 percent in 1990.

Researchers found that the number of adults identifying with noreligion more than doubled, from 14.3 million (8 percent) in 1990 to29.4 million (14.1 percent) in 2001.

The number of adults describing their religion as Jewish dropped from3.1 million to 2.8 million. An additional 2.5 million who said they hadno religion or identified with another religion have Jewish parents,were raised Jewish or consider themselves Jewish for some other reason.

Adults who described themselves as Muslim or Islamic totaled 1.1million, almost double the number in 1990. Twenty-three percent of thisgroup said they were black while the vast majority of the others saidthey were white or Asian.

The study was released in the same week that the American JewishCommittee announced new research it commissioned that estimates thatMuslims of all ages total about 1.8 million, far lower than currentestimates reported by some media of 5 million to 8 million. Tom Smith,director of the General Social Survey at the University of Chicago'sNational Opinion Research Center, said: "It is hard to accept estimatesthat Muslims are greater than 1 percent of the population, or2,814,000."

The American Muslim Council responded with an open letter to thecommittee saying it was disturbed that the Jewish organization "woulddeny the existence of four and a half million American Muslims."

The CUNY study was directed by Egon Mayer, a sociology professor atthe Graduate Center and Brooklyn College, and Barry Kosmin, who directedthe 1990 religion study.