You can find some sweet information out there on the interwebs. At Alas, a blog, one of my fave blogs, I came upon the following graphs. And I do love me some good graphs.
Commentary from the source of this graph, the Pew Global Attitudes Project:
The survey finds a strong relationship between a country’s religiosity and its economic status. In poorer nations, religion remains central to the lives of individuals, while secular perspectives are more common in richer nations.1 This relationship generally is consistent across regions and countries, although there are some exceptions, including most notably the United States, which is a much more religious country than its level of prosperity would indicate. Other nations deviate from the pattern as well, including the oil-rich, predominantly Muslim — and very religious — kingdom of Kuwait.
And some similar research on the US from Columbia University:
States that voted for Bush in 2004 are in red and the Kerry-supporting states are blue. You can see that people in richer states tend to be less religious, although the relation is far from a straight line. There is also some regional variation (more religious attendance in the south, less in the northeast and west).
Before leaping to conclusions, we must remember that this data only expresses correlation, not causation. Even so, I am intrigued by interpreting what this all means. What is it about high religiosity that pairs it so often with poverty? Are those with low quality of life more likely to turn to religion as a consolation, or does a high level of religiosity in a society somehow impede its ability to maintain a strong economy and stable society?