Washington DC, A massive study based on 35,000 telephone interviews across the country has found large numbers of Catholics have drifted away from their church either to other faith groups or dropping out entirely.

The “U.S. Religious Landscape Survey,” sponsored by the Pew Forum on Religion and Public Life, found that the Catholic church has suffered the greatest loss in absolute numbers, with approximately one-third of those raised Catholic saying they no longer belong to the church.

Close to 10 percent of all Americans, the survey notes, are former Catholics, most of whom find new homes in other churches.

“The disturbing findings of the Pew research underscores the urgency of reshaping the operative culture in many Catholic parishes and religious institutions to one in which people feel more valued and invested”, said Francis J. Butler, President of the philanthropic organization, FADICA. “Of the greatest urgency to a growing number of private, Catholic donors today, are programs and activities that welcome and enable broader numbers of believers, especially younger people, to exercise their gifts and grow in faith,” he added.

Despite massive membership attrition within U.S. Catholicism, the Pew study found that the Catholic church still represents one quarter of all religiously affiliated adults in the United States. The large size of the church’s membership, the study noted, was in no small part due to recent immigration. Pew reported that 45 percent of all Catholics eighteen to twenty-nine years of age are now Latino.

For the past three decades social research has tracked declining denominational engagement across the board, including mainline Protestants. Studies show that evangelical Christianity has grown as Americans have sought out more personalized faith communities.

“The Pew study is must reading for any concerned Catholic leader, especially foundations and donors who are helping Catholic institutions deal with the contemporary cultural challenges and changes within the religious landscape today, said Dr. Butler. "This research is a reminder that membership can be all too often taken for granted," he said, "whereas a religious culture of engagement is the key to the health and vitality of Catholic institutions.”

Copies of the Pew Study can be found at http://religions.pewforum.org