Time Magazine reports more than 85% of Americans follow a Christian faith and the largest segment of believers is evangelical Protestant (34% of Americans). In the past 40 years, evangelical Christians in the West have increased from 50 million to about 75 million, claims the Philadelphia Inquirer. In the rest of the world, the number shot up from 25 million to 325 million. Mainline Protestants make up 22% of the nation and Roman Catholics 21%.