Family Life Office personnel who coordinate marriage preparation in the Cincinnati archdiocese estimate that about 46 percent of new marriages are between Catholics and other Christians. National statistics are more elusive. Faithful to Each Other Forever, a 1989 handbook for marriage preparation issued by the National Conference of Catholic Bishops, indicates that 40 percent of American Catholics now enter interreligious marriages (not necessarily marriages between Catholics and other Christians, but between one partner who is Catholic and one who is not).
Regional figures vary greatly, according to Father Kilcourse. In the South, where the Catholic population is small, those statistics often climb as high as 75 percent, while in areas with a high Hispanic and traditionally Catholic population, the percentage plunges.
[...] Still, the numbers represent such a surge over the past 20 to 30 years that Church leaders struggle to name and define the phenomenon.
According to the 2006 Census, 60% of Catholics in the Diocese (aged above 25) were married, with 58% of these marriages between one Catholic and one non-Catholic.