Catholic pews in the US are emptying, according to data from a recent Gallup survey, which showed that Mass attendance is down to a 39 percent weekly average over the past 10 years.

From 2005-2008, Catholics reported attending Mass on a 45 percent average within seven days, but it has since dropped 6 percent from 2014-2017.  

The average Mass attendance in 1955 was at 75 percent, which roughly consisted of all age groups. During this time period, around three in four Catholics had attended Mass within the past week.  

But, that number is slowly changing, pointing to a historic shift in the Church, with some interesting percentages within the younger age groups.

"In particular, older Catholics have become less likely to report attending church in the past seven days," noted the Gallup study.

"For the first time, a majority of Catholics in no generational group attend weekly."

The age group with the highest number of weekly attendance was 60 and above demographic, with 49 percent. That number dropped from 59 percent over the past decade.

The younger demographic – aged 21 to 29 – saw a slight rise in weekly Mass attendance from 2005-2008 at 29 percent. This then dropped in 2014-2017 to 25 percent.

This rise and drop among the younger demographic is mainly due to the fact that younger adults are more likely in recent years to identify with non-Christian religions across the board. In 2016, Gallup reported that one in five Americans are associated with no religious identity at all.

"All of this come amid a broader trend of more Americans opting out of formal religion or being raised without it altogether," the survey said.

Interestingly, the next oldest demographic – aged 30-39 – saw a slight rise in attendance from 40 to 43 percent in the past ten years. This was the only age group with a boost in attendance.

The Gallup study did note that the decline in weekly Mass attendance has shown that the overall proportion of Americans identifying as Catholic is "holding fairly steady," which they attributed to the growth of the U.S. Hispanic population.  

The study also highlighted that weekly church attendance among Protestants has remained fairly steady at around 45 percent for the last ten years, although fewer Americans now identify as Protestant, dropping from 71 percent to 47 percent over the past 60 years.