The number of young people with no religious affiliation is continuing to grow, according to a new survey. 

The study by the Survey Center on American Life found that over a third (34%) of young adults in the US are now religious unaffiliated. 

And growing numbers have a close social connection with someone who is religiously unaffiliated - 42% today, up from 18% in 2004. 

Despite the lack of religious affiliation, many Americans actually believe in God (87%). 

But a majority of Americans (59%) do not believe that belief in God is necessary to be moral or have good values. 

The study also found that a significant number of Americans (54%) were not invited to church in the last 12 months or ever in their life. 

This is despite the survey uncovering a "strong relationship" between being invited to a service and actual worship attendance, with two-thirds (67 percent) of those invited in the past week reporting that they attended at least weekly or more often.

In stark contrast, only 14 percent of those who were never asked to attend said the same and nearly half (47 percent) of Americans who had never been asked say they never go.

The findings echo telephone surveys by the Pew Research Center in 2018 and 2019, which found that 65% of American adults described themselves as Christians, down 12 percentage points over the past decade.

At the same, the religiously unaffiliated share of the population - those describing themselves as atheist, agnostic or "nothing in particular" - rose from 17% in 2009 to 26% last year, according to Pew's research.