Figure 6. Statistical development of the percentages of Christian and Muslim populations with respect to the total population of North America as a whole from 1900 to 2010 (WCD)
From the above figure we can see a substantial decline in the percentage of Christians of about 18% through 2010 and a slight increase of 1% for Islam (Table 2). The decline of Christians is most notable in the Protestant denominations, and, indeed, despite the turmoil in recent years within the Roman Catholic Church, their numbers actually increased by about 10% through 2010. The trend in the decline of Protestants, although not as severe, seems to mirror that of Western Europe, probably for many of the same reasons: increased materialism, secularism, rationalism, rejection of the notion of spiritual authority outside of oneself, etc.
Since the UN does not sub-divide North America in regions, no further breakdown is given here.