For many Americans, religion—particularly Christianity—is intrinsically valuable. We appreciate religiously motivated behavior primarily because it honors God and serves our fellow man.

But an increasing number of our fellow citizens are agnostic about God and skeptical that religion provides much benefit to our neighbors. This summer a Pew Research survey found that while a majority of U.S. adults still say religious institutions contribute either “a great deal” (19 percent) or “some” (38 percent) to solving important social problems, four-in-ten (39 percent) now say religious institutions make little to no contribution in this area. A minority of religious “nones” (38 percent) say religious institutions contribute at least some help to solving social problems, compared with, for example, 65 percent of Protestants who say the same.

This skepticism about religion’s value to society lead researchers Brian and Melissa Grim to conduct a study, recently published in the Interdisciplinary Journal of Research on Religion, that shows how religion contributes to the U.S. economy. “Given the division of opinion on religion’s contribution to American society,” say the authors, “this present study seeks to shed light on the topic by making an estimate of religion’s socio-economic value to society. Indeed, we should know if the decline in religion is likely to have negative economic consequences.”

Their study provide three estimates of the value of faith to U.S. society. The first and most conservative estimate takes into account only the revenues of faith-based organizations falling into several sectors (education, healthcare, local congregational activities, charities, media, and food). The second estimate takes into account the fair market value of congregational social services and contribution of businesses with religious roots. Their third, higher-end estimate based on the annual household incomes of America’s religiously affiliated population.

By their most conservative estimate, the economic contribution of the religion sector to the U.S. society is roughly $378 billion a year: healthcare ($161.0 billion), local congregational activities ($83.8 billion), education ($74.0 billion), charities ($44.3 billion), media ($0.9 billion), and food ($14.4 billion).

Their second estimate shows a contribution of about $1.2 trillion. Faith-based healthcare networks contribute $161 billion annually (13.9 percent of the total contribution of religion to the U.S. economy). Congregations contribute about $327 billion annually (28.2 percent), plus an additional $91.3 billion if schools and daycare are taken into account (together making 36.1 percent of the total). Higher education adds $46.8 billion annually (4 percent), charities add $95.2 billion annually (8.2 percent), and businesses add $438 billion annually, slightly more than a third of the total (37.8 percent).

Their third estimate is based on recognition that “many, if not most people of faith, aim to conduct their affairs (to some extent, however imperfectly) guided by and inspired by their religious ideals.” This higher-end estimate is based on the household incomes of religiously affiliated Americans, and places the value of faith to U.S. society at $4.8 trillion annually, or the equivalent of nearly a third of America’s gross domestic product (GDP).

The study discuss the limitations of this type of research but note that it provides a “useful starting point for further studies of the socio-economic contributions of religion.”

By whatever estimate we use, though, the result provides support for the economic benefit of faith on society. “The data are clear,” say the researchers. “Religion is a highly significant sector of the American economy.”