Jeffrey M. Jones at Gallup:
The vast majority of U.S. adults believe in God, but the 81% who do so is down six percentage points from 2017 and is the lowest in Gallup's trend. Between 1944 and 2011, more than 90% of Americans believed in God.
Gallup's May 2-22 Values and Beliefs poll finds 17% of Americans saying they do not believe in God.
Gallup first asked this question in 1944, repeating it again in 1947 and twice each in the 1950s and 1960s. In those latter four surveys, a consistent 98% said they believed in God. When Gallup asked the question nearly five decades later, in 2011, 92% of Americans said they believed in God.
A subsequent survey in 2013 found belief in God dipping below 90% to 87%, roughly where it stood in three subsequent updates between 2014 and 2017 before this year's drop to 81%.
