What is the correlation between religiosity and social ills like abortion, teen pregnancy, sexually transmitted diseases, suicide and homicide?
The correlation is quite good. As The Times says:
According to the study, belief in and worship of God are not only unnecessary for a healthy society but may actually contribute to social problems.
The research paper that is the source for these claims has some wonderful charts on the topic. It's hard to pick a favorite, but I like this one:
Eschew free thought, critical thinking and intellectualism, and these are the tragic results you get.
Quoting paragraph 18 of the paper:
No democracy is known to have combined strong religiosity and popular denial of evolution with high rates of societal health. Higher rates of non-theism and acceptance of human evolution usually correlate with lower rates of dysfunction, and the least theistic nations are usually the least dysfunctional. None of the strongly secularized, pro-evolution democracies is experiencing high levels of measurable dysfunction.
Once again, thanks to Pharyngula for the link.