Having lunch one day, a sex therapist said to her friend, "According to a survey we just completed, ninety percent of all people masturbate in the shower. The other ten percent of them sing."
"Really?" asked the friend.
The therapist shook her head and proceeded to ask, "And do you know what the most popular song people sing in the shower?"
The friend shook her head and replied, "No."
The therapist replied, "I didn't think so."