95% of Adults Had Pre-Marital Sex?

CNN is reporting on a new study which claims 95% of all men and women since 1940 had pre-marital sex. This is used in the article to argue that abstinence programs are a waste of time, and that "safe sex" should be the focus on Federal funding since "most people will have pre-marital sex anyway."

More than nine out of 10 Americans, men and women alike, have had premarital sex, according to a new study. The high rates extend even to women born in the 1940s, challenging perceptions that people were more chaste in the past...
Finer is a research director at the Guttmacher Institute, a private New York-based think tank that studies sexual and reproductive issues and which disagrees with government-funded programs that rely primarily on abstinence-only teachings. The study, released Tuesday, appears in the new issue of Public Health Reports.
The study, examining how sexual behavior before marriage has changed over time, was based on interviews conducted with more than 38,000 people -- about 33,000 of them women -- in 1982, 1988, 1995 and 2002 for the federal National Survey of Family Growth. According to Finer's analysis, 99 percent of the respondents had had sex by age 44, and 95 percent had done so before marriage.
Even among a subgroup of those who abstained from sex until at least age 20, four-fifths had had premarital sex by age 44, the study found.

I realize that I am one of those the study would say is "in the minority" and probably deluded, but I find this study hard to believe. Of course, we don't know what they define as "sex" or where the pool of respondents came from. I am sure this will be a major point of discussion in the blogsphere over the next few weeks.