They are interesting statistics, Beso. Slightly surprised to see Ireland trending so high in the nations of the godless - was there an Irish emphasis to this report?
You always have to be careful interpreting opinion polls, because selection bias can be huge, but when you have an opinion poll conducted in the same fashion with the same questions over a number of years, such biases tend to be averaged out, and the trends emerge.
Those areas where you have a culture, heritage and history of a strong, almost evangelical church often coincide with those areas of the globe that struggle economically, so its not just poverty or education, but these factors definitely play a part.Study after study has demonstrated this trend - that religiousity declines with increasing education and wealth, and with female emancipation.
Education, female emancipation and cultural heritage are probably the factors that most influence a decline in religiousity, in my opinion.
One of the more interesting data points in my view is the persistence of religiosity in the USA, being distinctly more religious than its european or asian economic equivalents.