Fifteen percent of all U.S. adults have had four or more children, Pew found. This data was not broken down by income, education or other factors that significantly affect childbearing.

Members of some religious groups are a little bit more likely to have had at least four children: 17 percent of evangelical Protestants had at least four kids, and 18 percent of Catholics. Some are a little bit less likely: 9 percent of mainline Protestants had at least four children, and 12 percent of Jews. The Mormons are by far the outlier: 46 percent of Mormon adults have had at least four children.

So how do the non-religious stack up compared to religious people? Not so differently. Twelve percent of “nones” — the rapidly growing group of Americans who identify their religion as “nothing in particular” — have had at least four children.