Census

I was sitting on my porch when a young man walked up with a pad and pencil
in his hand. "What are you selling, young man?" I asked.

"I'm not selling anything," the young man said. "I'm the Census Taker."

"A what?" the man asked.

"A Census Taker. We are trying to find out how many people are in the
United States."

"Well," the man answered. "You're wasting your time with me, I have no
idea..."