Why would I believe this? The American Spectator is a magazine with a politically conservative agenda. Your article's author appears to have gotten his "data" from a Christian web site called the International Bulletin of Missionary Research, including such hard science as, "Atheists are thought to be 137 million, a declining number" and "These atheists are presumably disproportionately represented in the West".In 2011, the American Spectator citing research published in the International Bulletin of Missionary Research reported that atheism is on the decline as a whole in terms of adherents.
The American Spectator declared:
The report estimates about 80,000 new Christians every day, 79,000 new Muslims every day, and 300 fewer atheists every day. These atheists are presumably disproportionately represented in the West, while religion is thriving in the Global South, where charismatic Christianity is exploding."
"Thought to be"? "Presumably"?
How reliable is this Christian web site? Let them tell you themselves. They call themselves, "The reliable source for Christian mission history."
This is called Christian propaganda, and it's written to make you feel better about your church dying in the West. You can tell when it refers to all killed Christians as "martyrs," or when it includes language like the following:
"But overall, despite the distortions of secular, U.S. elite culture, people of faith in America and around the world can be hopeful that faith, and not Western secularism, represents the future for the vast majority of the world."
Mean old secular elites. Unlike the warriors for Jesus, they distort everything!