Friday, September 04, 2009

Median number of sexual partners: Feminist X makes a good point that we shouldn't assume that a given number of sexual partners now and in the past measures the same trait. The same guy who had two partners in the past might have 20 partners now.

My earlier analysis only covers the past three decades, so I think the period is short enough to assume that we're measuring the same thing in each of the three decades (80s, 90s, 00s). But it's always better to check.

The mean number of sex partners for white men ages 30 to 39 looks like it hasn't changed much since 1980, but the mean is a poor statistic to use because it is very sensitive to the handful of guys with many, many partners. The median is much better: it was seven partners in the 80s and 90s, and it's six in this decade. Cultural conditions don't seem to have changed much.


  1. Recently I compared men and women who are currently 36 and younger in the GSS with men and women who were 36 and younger in 1988-1990. I looked at sexual partner frequencies in the preceding year.

    There has been an increase in celibacy among both men and women, but also an increase in the number of multiple partnerships.

    A rise in the age of marriage predicts an increase in both celibacy and multiple partnerships, e.g. increased waiting/searching periods and accumulated marriage "substitutes" (short and long term relationships of various lengths).

    Given that married people have the most active and consistent sex lives (contrary to stereotype), there is probably a lot less sex going on than there used to be.


    0: 15.2//12.6
    1: 50.3//65.8
    2: 12.7//12.4
    3-4: 12.2//6.3
    5+: 9.6//2.9

    20 YEARS AGO

    0: 11.0//9.3
    1: 58.9//75.2
    2: 8.8//10.0
    3-4: 12.4//4.2
    5+: 8.9//1.3

  2. See here. The age of marriage has risen 4 years for women since 1980, and 2 years since 1990. 3 years for men since 1980, and 2 years since 1990.

  3. Anonymous10:05 AM

    One question to ponder is how many different sex partners in a year for a single person is too many? It's not as clear as it might seem. Okay, some cases are obvious: a man who's had two in a year is fine, while a man with 20 is a very different story. But what about 5+, the top category in the GSS? I would have to say that five in a year is not too many for a man; figure, if there's one relationship that ends during the year, another that begins, two quick flings, and a visit to the Happy Sunshine Oriental Wellness Spa, you're up to five, and spread out over 12 months it doesn't seem excessive. Perhaps for a woman, the same number might be on the high side, but I'll give her the benefit of the doubt.


  4. Peter,

    The numbers tell you how common or unusual a man with 5 sex partners a year is. For a single year it is about 1 in 10 men who are 36 and younger, as noted above.

    The median number of lifetime sex partners for men in almost all European countries (where promiscuity is highest) is 4.

    A man who consistently had 5 sex partners a year would rack up 100 sex partners over 20 years. 100+ lifetime sex partners is at about the 97th percentile for men.


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