Reader FeministX suggested that I take a look at the frequency of sex among white married couples by education. Here are the means for the past 30 days (N = 852):
Mean frequency of sexual intercourse in past 30 days
No degree 16.27*
High school 8.08*
Those with less than a BA have significantly more sex than couples with 4 or more years of education. At the extremes, married whites with no degree have three times as much sex as PhDs. Educated folks prefer the bookie to the nookie.