Jews in the United States are overwhelmingly proud to be Jewish, yet nearly one in five of them describe themselves as having no religion, according to a Pew Research Center survey published Tuesday.

The gap is generational, with 32 percent of Jews born after 1980 identifying as Jewish on the basis of ancestry, ethnicity or culture – compared with 93 percent of Jews born in 1914-27 who identified on the basis of their faith.

"This shift in Jewish self-identification reflects broader changes in the US public," said Pew's Religion and Public Life Project in a summary of its 210-page report.

"Americans as a whole – not just Jews – increasingly eschew any religious affiliation," with 22 percent of all Americans identifying with no particular faith, it said.

Nevertheless, 94 percent of respondents said they were proud to be Jewish, while seven out of 10 felt either very attached or somewhat attached to Israel, a proportion essentially unchanged since the turn of the 21st century, Pew said.

Forty percent believe that the land of Israel was “given to the Jewish people by God,” while 38 percent felt the Israeli government is making sincere efforts towards peace with the Palestinians, and 44 percent thought Jewish communities in Judea and Samaria harmed Israel's security interests.

The researchers included in their poll the 22 percent of Jews who describe themselves as having “no religion,” but who identify as Jewish because they have a Jewish parent or were raised Jewish, and feel Jewish by culture or ethnicity.

Based on this wide definition of “who is a Jew,” the poll found that the intermarriage rate has reached a high of 58 percent for all Jews, and 71 percent for non-Orthodox Jews — compared to just 17 percent before 1970. Two-thirds of Jews do not belong to a synagogue, one-fourth do not believe in God and one-third had a Christmas tree in their home last year.

Jews make up 2.2 percent of the American population, a percentage that has held steady for the past two decades. The survey estimates there are 5.3 million Jewish adults and 1.3 million children being raised at least partly Jewish. These estimates are close to those published in a different survey this week, which estimated that there are about 6.8 million Jewish adults and children in the US.

Pew interviewed 3,475 Jewish Americans by telephone from February 20 through June 13 for its study, giving a statistical margin of error of plus or minus three percentage points.

Release of the findings coincided with a visit to the United States by Israeli Prime Minister Binyamin Netanyahu.