The Association of Religion Data Archives (ARDA)
I stumbled accross this site. Those interested in comparative data regarding religious believes including JWs might find this interesting.
Here is the link:
About the ARDA
The Association of Religion Data Archives (ARDA) strives to democratize access to the best data on religion. Founded as the American Religion Data Archive in 1997 and going online in 1998, the initial archive was targeted at researchers interested in American religion. The targeted audience and the data collection have both greatly expanded since 1998, now including American and international collections and developing features for educators, journalists, religious congregations, and researchers.
If you know of a data collection that should be included in the Association of Religion Data Archives, please contact us using the addresses or phone number given below. If you would like to submit a data collection, please complete the Submission Form and send the data file, appropriate support material, and a completed submission form (including the authorization form) to our office.