The obvious (and apparently overlooked) flaw in this research is that getting a truthful answer from an average American 16 year old concerning sexual practices is essentially impossible.
Why would they all tell researchers that they had had one sexual relationship for the most part? Seems like they would attempt to exaggerate the numbers more than lessen them.
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See what other swarmers have to say about it. People love this place, so I feel fine about sending you there and am confident you will enjoy boners.