Summarizing data from surveys performed in 1991, 1998 and 2008 in 30 countries from Chile to Japan, the university’s National Opinion Research Center found that, on average, 43 percent of those aged 68 and older were certain that God exists.

By comparison, an average of 23 percent of people aged 27 and younger were firm believers in God, according to the report, which gathered data from the International Social Survey Program, a consortium of the world’s leading opinion survey organizations.

“Looking at differences among age groups, the largest increases in belief in God most often occur among those 58 years of age and older. This suggests that belief in God is especially likely to increase among the oldest groups, perhaps in response to the increasing anticipation of mortality,” researcher Tom Smith said in a statement.