A recent study reveals that the United States has become more secular over the years. While the majority of Americans still call themselves Christians, the second largest group follows no religion at all.

“Nones,” as the researchers call them, number 56 million in the U.S., reveals the Pew Research Center study, which was first done in 2007. The percentage of "Nones" was 16 percent that year, and reached 23 percent in 2014. The rise coincided with a decline among the followers of Christianity. While they were 78 percent at the beginning, the percentage fell to 71 percent by 2014. The nation, which was once largely Protestant, now has 46.5 percent Protestants.

According to the study, published Tuesday, seven out of 10 U.S. citizens still identify with traditional Christianity. There has been a growth of 7 percent in those who are agnostic, atheist or follow no particular religion.

Nevertheless, it has been debatable if people following no faith should be called secular. Experts argue that many of those people still believe in God or call themselves “spiritual.” The Associated Press reports that the new study finds there has been an increase in the number of secular people as well.

In 2007, 25 percent of the people with no religion said that they were agnostic or atheists. However, the number grew to be 31 percent in 2014. The percentage of people who considered religion to be vital to them fell.

The Los Angeles Times reported that the U.S. is still more religious than most developed countries. However, the increase in the number of people following no traditional religion echoes similar ideological trends in Europe.

Judaism is the most popular faith among non-Christian Americans. However, only around 2 percent of Americans identify themselves as Jewish. Other major non-Christian religions represented in the U.S. include Buddhism, Hinduism and Islam.

Contact the writer: s.mukhopadhyay@ibtimes.com.au