Approximately one-third of those who say they were raised Catholic no longer describe themselves as Catholic; which means that roughly 10% of all Americans are former Catholics. Other surveys — such as the General Social Surveys, conducted by the National Opinion Research Center at the University of Chicago since 1972 — find that the Catholic share of the U.S. adult population has held fairly steady in recent decades, at around 25%. What this apparent stability obscures, however, is the large number of people who have left the Catholic Church. Losses have been partly offset by the number of people who have changed their affiliation to Catholicism but more importantly by the disproportionately high number of Catholics among immigrants to the U.S. Read More

Russell Heimlich  is a former web developer at Pew Research Center.