‘I must question some of the numbers in this chart. First off, Nigeria is 50% Muslim, making a church attendance figure of 89% rather unrealistic, unless mosque attendance is counted. Ireland’s numbers look excessively high as well. While high church attendance numbers may have been characteristic of traditionally Catholic Ireland until about 40 years ago, the effects of secularism, liberal theology in the Catholic Church, and recent immigration from other countries (presently one out of ten residents of Ireland is of foreign origin) make the claim of 84% church attendance very suspect, certainly on a weekly basis. OTOH, the statistic for 2% church attendance in Russia seems low. This number may be based on a citation from the Russian Interior Ministry, which I found in Wikipedia, that said weekly church attendance is less than 2%. Even if his number on weekly attendance is accurate, the other statistics, including the one for the United States, may be based on monthly attendance.’
By all means question away, but unless you can provide figures with a similarly strong provenance from a respected source, you’re just guessing.
In any case, even if we assume the validity of the NationMaster statistics, numerous other researchers (Barna, Gallup) have shown that Americans adhere to major points of Christian doctrine at a higher percentage than Europeans, especially Western Europeans. If you were to calculate a weighted average of the Western European nations cited in the NationMaster chart, the church attendance figures in the U.S. would be higher. That being said, my main point was not an attack on European agnosticism and atheism but the clear evidence that American religious belief is heading in the direction of Western Europe.