are you counting orgasms
What about threesomes?
Indeed, unless one of them is cheating on the other
Then the opposite sex is still keeping things in balance. I think it's worth clarifying, though, that straight men and straight women have the exact same amount of straight sex.
Good point. I concede
This is not a one to one function
For all heterosexual sex it is a direct X : Y relationship
Yes X1 might have sex a lot more than X2 however the acts of X:Y will be perfectly equal.
Ah, but you didn't account for straight women who have sex with other straight women.
Yeah, on average, but see below about the median.
On average, yes of course, but the median amount of straight sex for men is higher than the median for women because there are more female prostitutes servicing many men than vice-versa.