For the first time since the late 1930s, fewer than half of Americans say they belong to a church, synagogue, or mosque, according to a new report from Gallup. Forty-seven percent of Americans now say they belong to a house of worship, down from 70 percent in the mid-1990s and 50 percent in 2019. The decline is part of a continued drop in membership over the past 20 years, according to Gallup data.