Religious fervor & societal happiness

I'd be curious to see a study linking religious fervor (and penetration) to economic success and societal happiness.

My guess is that the lower the former is, the higher the later becomes. Look at Haiti for example or any middle eastern or east Asian country that is under religious rule. For a happier, less crowded and more responsible world, religion should be totally eradicated, at least the one that's blended with government. You could tell me that Utah is just the opposite, but that's perhaps the exception that confirms the rule; at any rate (no pun intended) those Mormons Leaders are in it for the money, not the dogma!