It varies greatly for a myriad of reasons. Most of the time, at least two or three times a week given that we aren't too tired or not in the mood due to outside reasons. We've been together for three years, just for the record.
We're very physically and verbally affectionate with one another, however, so even through our sexual 'dry spells' we still feel very close to one another.
I've had the same partner for a year and a half, but I still voted. We have sex almost every day. Usually, we only don't have sex if we're totally exhausted. It's the first time I've been with someone who has a sex drive as high as mine, and I love it.