Sep 10, - 30 to 39 year olds have sex 86 times per year, which averages out at times per week. Things go slightly downhill from here. Those in the 40 to 49 age group manage to have sex only 69 times per year. Mar 7, - The average adult enjoys sex 54 times a year, or a little more than once a week, Twenge's data show. While married couples under the same roof don't fool around quite as much, they still have sex about 51 times each year.