Co-Habitation: During the period which they were single, 33% of American adults have lived with someone of the opposite gender, other than family or relatives. 39% of men and 28% of women have cohabited. Age seems to be a critical factor.
Co-Habitation By Age
Age % who have cohabited
Under 35 44%
35-49 33%
50-69 24%
70 & older 1%
Faith is another determining factor. Among born-again Christians of all ages, only 25% have co-habited. With people who call themselves Christians, but do not classify themselves as born-again, the rate is 37%; 42% of adults who associate with a faith other than Christian and 51% of atheists have done so. (Barna Research 8/6/01)
http://garydfoster.com