A year ago, I looked at the number of sexual partners American men have had over the last couple of decades to see whether or not a trend towards greater sexual promiscuity and general activity, as the Game narrative contends is the case, would be empirically detectable. The data, however, reveal that it has been steady state over that period of time.
This came in the wake of having found it to be clear that men with fewer partners (but at least one, obviously) are the most procreatively successful. I'm skeptical of the conceptualized alpha-beta dichotomy, but when it comes to reproduction, the betas are coming out on top. I've also attempted to measure alpha traits by race, finding a far higher percentage of alpha traits among black men than among white or Hispanic men, and have shown that men who say they would suffer in the place of their lovers (surely a beta move) have more children than men who say they would not (why suffer for a girl when I can just as easily find another one?)
I'm certain I'd planned on doing the same for women, but as I was entering my late-twenties at the time, senility must have kicked in and kicked it off my mental to-do list. Through the miracle of fish oil tablets and yoga*, it found its way back on that list, slated for completion rather than misplacement this time around.
The following graph shows the percentage of all women aged 21-45 by the number of different partners they've had through the course of their adult lives. It's a bit difficult to decipher at first blush, but the ranges are mutually exclusive so that in each year the total percentage of all women falling into one of the six categories based on number of partners comes to 100:
There is an evident decline in the number of women sticking with a single partner over time, corresponding to increases in the percentages of women reporting no and 6-10 partners. Excepting a seemingly random spike in 1996, the trends are pretty continuous. The decline in the number of women with a single partner is presumably a result of the decline in marriage rates over the same period of time, with women who would've married in the past engaging instead in a series of monogamous relationships, or forgoing sex entirely.
The next graph shows the frequency with which women aged 21-45 have had sex over time:
There has been a gentle decrease in the percentage of women having sex at least once a week, as indicated by the light blue and red lines, and a corresponding increase in the percentage getting freaky less often than that. As women have more sex when they're married or in a relationship than when they're not, the decline in marriage rates predictably seems to correspond with a decrease in overall female sexual activity.
In summation, the story over the last couple of decades for women in the US is a slight increase in variety and a slight decrease in frequency.
For objections about the reliability of the data, see here. The consistent discrepancy between male and female self-reported numbers indicates that at least one sex persistently fudges the figures. Veracity may be couched somewhere in between, or simply come out of the mouths of men. Unless the argument is that there has been a change in the degree to which women low-ball and/or men overstate the numbers over time, though, that question is irrelevant to what is reported here.
If anything, I'd guess the female tendency towards understatement is declining, as the social stigmas (especially those of a religious bent) surrounding more active and wide-ranging sexual behaviors of all kinds have been relentlessly whittled away.
GSS variables used: SEXFREQ(1)(2)(3-4)(5)(6-7), NUMMEN(0)(1)(2-5)(6-10)(11-19)(20-250), AGE(21-45), SEX(2), YEAR
* Okay, I'll confess to having only done a yoga routine once in my life (albeit in the last year!), finding it far too slow and light for my tastes. Resistance? Hell yes. Isometrics? Sure. But let's confine stretching to the first three minutes, please!