The most common religious identity among Americans ages 18 to 29 is “none,” according to a report from the conservative-leaning think tank American Enterprise Institute (AEI). More than one-third of young adults (34%) surveyed identified as religiously unaffiliated ― telling researchers they were atheist, agnostic or “nothing in particular.”

There seems to be a generational divide over questions about God, likely influenced by the rise of these young “nones.” As a whole, young adults were much more likely to express uncertainty about God. Only 39% of young adults said they were absolutely certain God exists, compared with 61% of seniors 65 and older, according to a HuffPost analysis of the report’s data.

Researchers also documented a modest difference between young and older Americans over whether people need God to be good. Thirty-four percent of young adults said it was necessary for a person to believe in God to be moral and have good values, while a higher percentage of seniors, 43%, said the same.