(A church near the Derryveagh Mountains in County Donegal, Ireland, February 24, 2011. REUTERS/Cathal McNaughton)

Traditionally Catholic Ireland has registered almost the steepest drop worldwide in people calling themselves religious in a new survey tracking international trends in faith and atheism in recent years. Only 47 percent of Irish polled said they were religious people, a 22-point drop from the 69 percent recorded in the last similar poll in 2005, according to the WIN-Gallup International network of opinion pollsters.

Average religiosity in the 57 countries included in the poll was 59 percent, a decline of 9 points since 2005, it said.

At the same time, the number of people declaring themselves to be convinced atheists rose from 4 percent worldwide in 2005 to 7 percent this year. The biggest growth was in France.

Sinead Mooney, deputy managing director of the RED C Research company in Dublin that conducted the Irish poll, cited two factors that put Ireland just behind Vietnam as the country where religious feeling fell off most steeply.