According to a Pew Research Center study released Tuesday, Americans who don't affiliate with a particular religion has grown to 56 million in recent years, making the 'none' faith group the second-largest in total numbers behind evangelicals.
Yes Christianity is still the biggest faith by far in the U.S., with 7 in 10 Americans identifying with the tradition. Yet the ranks of Christians have declined as people leave the religion and ascribe to nothing instead.
Pew conducted two major surveys of U.S. religious life, between 2007 and 2014. Americans who described themselves as atheist, agnostic or of no particular faith grew from 16 percent to nearly 23 percent.
While this was happening, Christians dropped from about 78 percent to just under 71 percent of the population.
The Pew researchers have long debated whether people with no religion should be defined as secular since the classification includes those who believe in God or consider themselves "spiritual."
The new Pew study found increasing signs of secularism.
Last year, 31 percent of "nones" said they were atheist or agnostic, compared to 25 percent in 2007. Along with this change, the percentage who said religion was important to them also dropped.
Pew's associate research director, Greg Smith, said the findings "point to substantive changes" among those who claim no religion, not mearly a shift in how people describe themselves.
The rise of "nones" has political significance. People with no religion are likely to vote Democratic, while white evangelicals are likely to vote Republican.
The Pew study found a drop of about 1 percent in the evangelical share of the population, which now comprises a quarter of Americans. Yet the overall number of evangelicals rose to about 62 million people, meaning they are still growing yet losing market share.
The "America's Changing Religious Landscape" survey was conducted on 35,000 people in English and Spanish from June 4th through Sept. 30th of 2014. The survey has a margin of error of plus or minus 0.6 percent.