A recently released study by PEW suggests that the "Christian share of the U.S. population is declining, while the number of
U.S. adults who do not identify with any organized religion is growing. Moreover, these changes are taking place across the religious landscape,
affecting all regions of the country and many demographic groups. While
the drop in Christian affiliation is particularly pronounced among
young adults, it is occurring among Americans of all ages. The same
trends are seen among whites, blacks and Latinos; among both college
graduates and adults with only a high school education; and among women
as well as men"
Unfortunately the most recent local data available is from 2010 and mainly comes through the Association of Religion Data Archives. It is a great piece of data but limited to five years ago.
We have done several post on this topic including the following:
Religious Traditions and SubFamilies for Herkimer and Oneida Counties
The Regional Decline of Religious Adherents: 1980 Versus 2010
Religious Adherents by County
Second Most Common Religious Following By State and County