A new study says that undocumented immigrants to the U.S. tend to be more Christian than the general population, while new legal permanent residents tend to be less Christian.

The Pew Research Center estimated that 83 percent of undocumented immigrants are Christian, with most coming primarily from Latin America and the Caribbean. As of 2011, there were about 11.1 million unauthorized immigrants in the U.S.

Christians make up just under 80 percent of the U.S. population.

The percentage of legal Christian immigrants has decreased from 68 percent in 1992 to 61 percent in 2012. There were an estimated 620,000 legal Christian immigrants in the U.S. in 2012.

As of 2012, about ten percent of legal immigrants are Muslim, an increase of five percentage points since 1992. Seven percent are Hindu, more than double their representation in 1992. About six percent are Buddhist, a one percent decrease since 1992. About 14 percent have no religious affiliation, a figure which has remained steady since 1992.

Pew attributes the changes since 1992 in part to a geographic shift in the sources of legal immigration.

The percentage of new legal immigrants from Europe, Latin America and the Caribbean or North America has declined, while the percentage from the Asia/Pacific region, the Middle East, North Africa and sub-Saharan Africa has increased.

The Pew Research Center's findings draw from several studies and U.S. government data. Some of the studies are based on estimates, in part because the U.S. government does not keep official data on religious affiliation of new permanent residents.