The more a Christian church becomes “multiracial,” the quicker its attendance drops and the institution declines, a new study has shown.

The report, published in the latest issue of the Journal for the Scientific Study of Religion, focused on the Evangelical Lutheran Church in America (ELCA).

Titled “Congregational Diversity and Attendance in a Mainline Protestant Denomination,” the study looked at data taken from 10,000 congregations in the ELCA, and the relationship between changes in racial/ethnic diversity and changes in average weekly attendance over a 19-year time period (1993–2012).

The study found that “racial diversity” doubled in the ELCA over that time period—and that “in spite of the ELCA’s denominational push for racial diversity in its local churches,” data showed that “increasing racial diversity associated with decreasing average attendance.”

Kevin Dougherty, an associate professor of sociology at Baylor and lead author on the study, said the findings shows congregations “trying to change their diversity” experience great difficulty surviving.

The study also found that:

– Rises in racial diversity were associated with declines in weekly attendance, especially in the 1990s.

– Older congregations were more likely to see a decline in attendance.

– Congregations in predominantly white communities were more likely to grow.

The ELCA is one of the least racially diverse denominations in the US, according to the Pew Research Center, with white people making up 96 percent of its membership.

Only the National Baptist Convention, with 99 percent black membership, is less diverse.

According to a Gallup poll published in December 2015, three-quarters of American adults identify with a Christian religion, little changed from 2014, but down from 80 percent eight years ago. That study was race-blind.

About 5 percent of Americans identify with a non-Christian religion, while 20 percent have no formal religious identification, which is up five percentage points since 2008.