Sexual statistics
 

A businessman boards a flight and is lucky enough to be seated next to an absolutely gorgeous woman. They exchange brief hellos and he notices she is reading a manual about sexual statistics. He asks her about it and she replies, "This is a very interesting book about sexual statistics. It identifies that American Indians have the longest average penis and Polish men have the biggest average diameter. By the way, my name is Jill. What's yours?"
He coolly replies, "Tonto Kowalski, nice to meet you."