The Pew survey finds that constant movement characterizes the American religious marketplace, as every major religious group is simultaneously gaining and losing adherents. Those that are growing as a result of religious change are simply gaining new members at a faster rate than they are losing members. Conversely, those that are declining in number because of religious change simply are not attracting enough new members to offset the number of adherents who are leaving those particular faiths.
To illustrate this point, one need only look at the biggest gainer in this religious competition – the unaffiliated group. People moving into the unaffiliated category outnumber those moving out of the unaffiliated group by more than a three-to-one margin. At the same time, however, a substantial number of people (nearly 4% of the overall adult population) say that as children they were unaffiliated with any particular religion but have since come to identify with a religious group. This means that more than half of people who were unaffiliated with any particular religion as a child now say that they are associated with a religious group. In short, the Landscape Survey shows that the unaffiliated population has grown despite having one of the lowest retention rates of all “religious” groups.