“Americans have long been viewed as exceptionally religious compared to other nations in the developed world,” said Philip Brenner, a research fellow at the U-M Institute for Social Research (ISR) and the author of the study. “But this study suggests that American religiosity may be exceptional not in terms of actual behavior, but rather in terms of identity.

“In the U.S., and to a lesser extent in Canada, the gap between what we say and what we do is substantial, and has been so for the last several decades.”…

While conventional survey data show high and stable American church attendance rates of about 35 to 45 percent, the time diary data over the past decade reveal attendance rates of just 24 to 25 percent — a figure in line with a number of European countries.

America maintains a gap of 10 to 18 percentage points between what people say they do on survey questions, and what time diary data says they actually do, Brenner reports.