So many Americans claim no religion at all (15%, up from 8% in 1990), that this category now outranks every other major U.S. religious group except Catholics and Baptists. In a nation that has long been mostly Christian, "the challenge to Christianity … does not come from other religions but from a rejection of all forms of organized religion," the report concludes
No religion is steadily gaining ground all religions are losing ground to the non-religious. Non-religious has a massive retention rate and good inflow. Religions like the Jehovah Witnesses have pretty consistent inflow rate and outflow rate and thus lose barely break even even with the hard selling. Wicca to her credit actually gains a lot and keeps them pretty well. All in all it seems we're getting progressively less stupid as time goes on. But, I'm sure when the hard times hit people will flock to religions.
| Religion | # in million | 1990 percent | 2008 percent | Change |
| Catholic | 57.2 | 26.2% | 25.1% | -1.1% |
| Baptist | 36.1 | 19.3% | 15.8% | -3.5% |
| No religion | 34.2 | 8.2% | 15.0% | 6.8% |
| Christian, generic | 32.4 | 14.8% | 14.2% | -0.6% |
| Mainline Protestant | 29.4 | 18.7% | 12.9% | -5.8% |
| Don't Know/Refused | 11.8 | 2.3% | 5.2% | 2.9% |
| Pentecostal/Charismatic | 8.0 | 3.2% | 3.5% | 0.3% |
| Protestant denominations | 7.1 | 2.6% | 3.1% | 0.5% |
| Mormon/latter-day Saints | 3.2 | 1.4% | 1.4% | 0.0% |
| New movements (such as Wiccan), other religions | 2.8 | 0.8% | 1.2% | 0.4% |
| Jewish | 2.7 | 1.8% | 1.2% | -0.6% |
| Eastern religions | 2.0 | 0.4% | 0.9% | 0.5% |
| Muslim | 1.4 | 0.3% | 0.6% | 0.3% |
